Abstract Microplastics and nanoplastics (MNPs) are environmental contaminants increasingly detected in human tissues, raising public health concerns. Although evidence is still insufficient to directly link MNPs to genitourinary cancers (GU), this Review examines their potential role in prostate, bladder, and renal cell carcinoma. Proposed mechanisms include chronic inflammation, oxidative stress, genotoxicity, and endocrine disruption driven by plastic-associated additives. Emerging studies report quantitative detection of MNPs within human prostate and bladder tumors, with higher burdens associated with dietary habits such as frequent take-out food consumption. The Review also highlights their role in cancer therapy: MNPs may alter antineoplastic drug pharmacokinetics and promote resistance, yet polymer-based nanoparticles can be engineered as advanced drug delivery platforms. Materials such as PLGA and PEG may improve targeted delivery of chemotherapies and immunotherapies, supporting more effective and personalized treatment strategies in GU oncology.
Bisphenol A (BPA) is a widespread endocrine disruptor that interferes with metabolism in humans and animals by inducing oxidative stress, lipid peroxidation, and cell death. Probiotics, conversely, have shown potential in promoting host health and reducing the toxicity of endocrine-disrupting chemicals (EDCs). This study examined whether sub-chronic BPA exposure disrupts hepatic lipid metabolism in female zebrafish (Danio rerio), and whether co-administration of probiotics mitigates these effects. Adult females were exposed for 28 days to the following treatments: 10 µg/L BPA via water (BPA); 109 CFU/g body weight/day of probiotic formulation (P); and both treatments (BPA+P). An untreated group served as a control (CTRL). Hepatic lipid composition was analyzed using UHPLC-QTOF-MS, while liver sections were investigated by Fourier Transform Infrared Imaging (FTIRI) spectroscopy. BPA exposure decreased 14 unsaturated triacylglycerols and lysophosphatidylcholine 18:0, suggesting steatosis onset and inflammation, while in the group exposed to BPA+P, the decrease was limited to 8 triacylglycerols and the reduction in lysophosphatidylcholine 18:0 was prevented. Analyses of pooled liver samples precluded modeling tank-level effects; thus, the results are interpreted as semi-quantitative. Partial least square discriminant analysis built on the comparison of all groups together confirmed an intermediate phenotype for BPA+P fish between BPA and P groups. The observed beneficial role of probiotics in counteracting BPA-related metabolic disturbances was also supported by FTIRI, evidencing the ability to mitigate the effects of BPA on lipid and glycosylated compound metabolism. These findings highlight the potential of probiotic supplementation as a practical and accessible strategy to mitigate BPA-induced metabolic disturbances, contributing to the development of mitigating approaches against environmental contaminant-related liver dysfunction.
Cisplatin is a platinum-based chemotherapy drug with antimicrobial and antitumoral activity, largely used for a long time in the treatment of several cancers, including the Oral Squamous Cell Carcinoma (OSCC), which is one of the most frequent neoplasms of the oral cavity. Due to its aggressiveness and metastatic invasion, OSCC is characterized by poor outcome, often related also to chemoresistance mechanisms. The intracellular enzyme paraoxonase-2 (PON2) normally acts defending cells from the damages induced by Reactive Oxygen Species. Hence, in cancer cells, this enzyme can shield the potential of cisplatin, triggering a resistance mechanism. Based on this evidence, PON2 knockdown seems to be a valuable way to enhance the effects of chemotherapy, escaping this resistance. In this study, HOC621 and HSC-3 OSCC cell lines submitted to PON2 silencing were analyzed by Fourier Transform Infrared Microspectroscopy to evaluate the time-dependent changes occurring in these cells after cisplatin treatment. Spectral data were statistically analyzed by multivariate and univariate analyses and compared with MTT results. Positive feedback on cisplatin efficacy was found in both cell lines submitted to PON2 knockdown, even if with a different response. In particular, a less growth was found in PON2 silenced HOC 621 cells, respect to HSC-3 ones. Moreover, specific spectral markers (A 1172 /A TOT , A 1053 /A TOT , A 967 /A 1080 , and A 992 /A TOT band area ratios) were identified and statistically analyzed (p < 0.05): cellular alterations mainly in nucleic acids and carbohydrates were found in both cell lines, although more evident in HOC 621 ones, which therefore appeared to be more affected by chemotherapy treatment.
The Adriatic Sea is a critical neritic habitat for juvenile and adult female loggerhead sea turtles (Caretta caretta), where intense anthropogenic pressures and environmental stressors may influence their reproductive biology. Knowledge on the onset of puberty in this population is limited by scarce information on the sub-adult stage, a transitional phase in which reproductive competence is acquired. This study integrated histological analysis and Fourier-transform infrared (FTIR) imaging spectroscopy to provide both structural and biochemical characterization of folliculogenesis, with emphasis on vitellogenesis, in C. caretta from the north-central Adriatic Sea. Histological analysis determined the progression of follicle development, while FTIR imaging, a label-free and spatially resolved technique, mapped the distribution of proteins, lipids, and nucleic acids across ovarian compartments. Logistic regression estimated the size at which 50% of females are sexually mature (L50) at 58.54 cm Curved Carapace Length (CCL). Based on this value, 60% of sub-adult females were already mature, indicating earlier puberty than previously inferred from macroscopic criteria. These preliminary results, along with reports of sporadic nesting in the Adriatic, raise the question of whether this basin may host further nesting events in the future. FTIR imaging proved to be a powerful tool for reproductive biology in non-model marine vertebrates.
Background: The study exploited, for the first time, Attenuated Total Reflectance-Fourier Transform-InfraRed (ATR-FTIR) spectroscopy on human dental pulps at different timings of root resorption (RR) to deepen the biological mechanisms occurring in deciduous teeth (De) during their replacement with permanent ones. Methods: N:36 dental pulps from sound De were divided into the following: G0 (no RR); G1 (RR less than 1/3 of root length); G2 (RR not exceeding 2/3 of root length); and G3 (RR more than 2/3 of root length). Samples were analyzed by ATR-FTIR, and the spectral data were submitted to univariate (One-way ANOVA and Tukey’s multiple comparison tests; statistical significance set at p < 0.05) and multivariate (Principal Component Analysis, PCA) analyses. Results: PCA displayed good discrimination among groups, ascribable to: (i) the intensity of the peaks of nucleic acids (~1715 cm−1, ~1237 cm−1, ~964 cm−1, and ~815 cm−1) and carbohydrates (~1159 cm−1) which increased from G0 to G3 (p < 0.05); (ii) the relative amount of lipids which decreased from G0 to G3 (p < 0.05); and (iii) the intensity of the peaks at ~1014 cm−1, and ~875 cm−1 (phosphates and carbonates in hydroxyapatite), which decreased from G0 to G3 (p < 0.05). Conclusions: This study confirmed ATR-FTIR as a reliable and quick technique for the characterization of the dental pulp and highlighted a correlation between specific molecular changes in the dental pulp of deciduous teeth and different RR stages, shedding new light on this process and paving the way for future research, which could improve the clinical management of the primary dentition.
Hydrogels are interesting materials with potential applications in the treatment of water contaminated by organic and inorganic toxic compounds. Among the different monomers/polymers commonly used, the natural polymer lignin is undoubtedly an attractive candidate due to its biocompatibility, biodegradability, low toxicity, and availability in high quantities as the main by-product of the pulp industry. In the present work, the synthesis and characterization of a lignin-based hydrogel are described and tested in the adsorption of the nonsteroidal anti-inflammatory drug, diclofenac, one of the so-called emerging contaminants. Due to the anionic nature of diclofenac currently used in pharmaceutical preparations, a cationic functionality is included in the polymeric backbone. The obtained hydrogel is characterized by a porous structure, thermal stability, and an elastic behavior more pronounced than the viscous one. It has a high swelling capacity and is able to efficiently remove diclofenac in batch mode, following a pseudo-second order kinetic, and adsorption could be well described by Langmuir and Sips isothermal models. For the first time, diclofenac removal by a lignin-based hydrogel is also carried out in a packed-bed column with a maximum capacity of ca. 50 mg/g, and different theoretical models are used to fit the experimental data.
Human pharmaceuticals represent a major challenge in natural environment. A better knowledge on their mechanisms of action and adverse effects on cellular pathways is fundamental to predict long-term consequences for marine wildlife. The FTIRI Imaging (FTIRI) spectroscopy represents a vibrational technique allowing to map specific areas of non-homogeneous biological samples, providing a unique biochemical and ultrastructural fingerprint of the tissue. In this study, FTIRI technique has been applied, for the first time, to characterize (i) the chemical building blocks of digestive glands of Mytilus galloprovincialis, (ii) alterations and (iii) resilience of macromolecular composition, after a 14-days exposure to 0.5 µg/L of carbamazepine (CBZ), valsartan (VAL) and their mixture, followed by a 14-days recovery period. Spectral features of mussels digestive glands provided insights on composition and topographical distribution of main groups of biological macromolecules, such as proteins, lipids, and glycosylated compounds. Pharmaceuticals caused an increase in the total amount of protein and a significant decrease of lipids levels. Changes in macromolecular features reflected the modulation of specific molecular and biochemical pathways thus supporting our knowledge on mechanisms of action of such emerging pollutants. Overall, the applied approach could represent an added value within integrated strategies for the effects-based evaluation of environmental contaminants.
Background One of the main factors for the osseointegration of dental implants is the development of an adequate soft tissue barrier, mainly composed by collagen, which protects the implant from bacterial development. The structural features of the peri-implant collagen are influenced by the implant components and, in particular, by the type of the surface. In the clinical practice, healing abutments are characterized by smooth surfaces, named machined. Recently, a new laser technique, Synthegra, has been developed to obtain a topography-controlled surface with micrometric regular pores that seems reducing the risk of peri-implantitis. Based on this background, this study aims investigating the structural organization and spatial distribution of collagen surrounding healing abutments characterized by laser-treated and machined surfaces. Methods Gingiva portions surrounding custom-made healing abutments (HA), characterized by alternated laser-treated and machined surfaces, were collected and analyzed by combining Fourier Transform InfraRed Imaging (FTIRI) spectroscopy, a non-invasive and high-resolution bidimensional analytical technique, with histological and multivariate analyses. Results Masson’s trichrome staining, specific for collagen, highlighted a massive presence of collagen in all the analyzed samples, evidencing a surface-related spatial distribution. The nature of collagen, investigated by the FTIRI spectroscopy, appeared more abundant close to the laser-treated surface, with a perpendicular disposition of the bundles respect to the HA; conversely, a parallel distribution was observed around the machined surface. A different secondary structure was also found, with a higher amount of triple helices and a lower quantity of random coils in collagen close to the laser treated surfaces. Conclusions FTIRI spectroscopy demonstrates that the use of a laser treated transmucosal surface can improve the morphological organization of the peri-implant collagen, which presents a distribution more similar to that of natural teeth. Trial registration : This trial is registered with ClinicalTrials.gov Identifier: (Registration Number: NCT05754970). Registered 06/03/2023, retrospectively registered, https://clinicaltrials.gov/show/NCT05754970 .
A crucial issue in forensics is determining the post-mortem interval (PMI), the time between death and the finding of a body. Despite various methods already employed for its estimation, only approximate values are currently achievable. Vitreous humor (VH) is an avascular tissue between the lens and the retina, mainly composed by a collagen fibers network, hyaluronic acid, and hyalocytes. Recently, it has received interest in forensic medicine, being easy to collect and susceptible to low microbiological contamination and putrefaction. Based on this evidence and thanks to the ability of Attenuated Total Reflectance - Fourier Transform InfraRed (ATR-FTIR) spectroscopy to perform fast analyses on a minimal sample amount, in this study, a new analytical approach to reliably estimate PMI is proposed combining ATR-FTIR analysis of VH human samples with multivariate statistical procedures, such as Principal Component Analysis (PCA) and Partial Least Squares-Discriminant Analysis (PLS-DA), for discriminant classification. Regression procedures, including Partial Least Squares Regression (PLSR), were performed: extremely positive results were obtained, and the most discriminant spectral features were highlighted (peaks at 1665, 1630, 1585, 1400, 1220, 1200, 1120, 854, 835, and 740 cm-1) and associated to PMI classes (average accuracy over 80 %). Specific and reliable markers able to correlate the macromolecular composition of VH with the PMI were identified, revealing a post-mortem protein degradation and amino acids deamination (decrease of proteins and increase of free amino acids and NH3), an increase of lactate, which diffuses from the retina to the VH, and changes in the hyaluronic acid component.
Elasmobranchs have an ancestral reproductive system, which offers insights into vertebrate reproductive evolution. Despite their unchanged design over 400 million years, they evolved complex mechanisms ensuring reproductive success. However, human activities induced a significant decline in elasmobranch populations worldwide. In the Mediterranean basin, the smooth-hound shark (Mustelus mustelus) is one of the species that are considered vulnerable to human activities. Conservation efforts necessitate a thorough understanding of its reproductive strategy. This study focused on mature male specimens of smooth-hound sharks that were captured in the Adriatic area and successively analyzed to provide, for the first time, a histologically detailed description of testicular development in the species. Seven phases of the spermatogenesis process were identified, along with the macromolecular characterization of cells obtained using Fourier-transform infrared imaging. Histological analysis showed structural and cellular features similar to those documented in the spermatocysts of other elasmobranchs. The examination of the evolution and migration of both germinative and Sertoli cells at each phase revealed their close connection. Furthermore, different expression levels of lipids, proteins, and phosphates (DNA) at each spermatogenesis stage were observed. This research provided new information on spermatogenesis in the common smooth-hound shark, which is crucial for conservation efforts against population decline and anthropogenic pressures.
The increasing global concern over microplastic pollution has driven a surge in research efforts aimed at detecting microplastics across various ecosystems. Airborne microplastics (MPs) have been identified in remote environments worldwide, including Antarctica. However, data on bulk atmospheric deposition remain scarce. From January to December 2020, atmospheric deposition was directly collected using passive samplers placed in eight sites across Victoria Land. Using Raman Microspectroscopy, MPs were identified in six out of the seven samples collected (one sample was lost due to the extreme weather conditions). The average daily MP deposition for Victoria Land was 1.7 +/- 1.1 MPs m(-2) d(-1), with values ranging from 0.76 to 3.44 MPs m(-2) d(-1). The majority (53 %) of MPs found in the atmospheric deposition were in the size class of 5-10 mu m, and the main shape of MPs was fragments (95 %). The predominant plastic type was polypropylene (31 %), followed by polyethylene (19 %) and polycarbonate (12 %). Polystyrene, polyester, styrene and polyethylene terephthalate each accounted for similar to 6 %. Microplastics identified in the coastal sites may have local origins, potentially associated with scientific activities at research stations. Conversely, a backward trajectories analysis suggested a potential contribution of atmospheric transport to microplastic deposition at Larsen Glacier and Tourmaline Plateau, the two most remote sites of the study area, where the highest MP concentrations were detected. Our findings present the first evidence of microplastics in the Antarctic atmospheric deposition directly collected via passive samplers, highlighting the need for continued monitoring and research to assess the environmental impact of MPs, particularly in sensitive and remote ecosystems like Antarctica.
High resolution analysis of collagen bundles could provide information on tumor onset and evolution. This study was focused on the microarchitecture and biomolecular organization of collagen bundles in oral tongue squamous cell carcinoma (OTSCC). Thirty-five OTSCC biopsy samples were analyzed by synchrotron-based phase-contrast microcomputed tomography and Fourier transform infrared imaging (FTIRI) spectroscopy. PhC-microCT evidenced the presence of reduced and disorganized collagen in the tumor area compared to the extratumoral (ExtraT) one. FTIRI also revealed a reduction of folded secondary structures in the tumor area, and highlighted differences in the peritumoral (PeriT) areas in relation with the OTSCC stage, whereby a significantly lower amount of collagen with less organized fibers was found in the PeriT stroma of advanced-OTSCC stages. Interestingly, no significant morphometrical mismatches were detected in the same region by PhC-microCT analysis. These results suggest that biomolecular alterations in the OTSCC stroma temporally anticipate structural modifications of collagen bundle microarchitecture.
ATR-FTIR (Attenuated Total Reflectance Fourier Transform InfraRed) spectroscopy, combined with chemometric, represents a rapid and reliable approach to obtain information about the macromolecular composition of food and plant materials. With a single measurement, the chemical fingerprint of the analyzed sample is rapidly obtained. Hence, this technique was used for investigating 13 differently processed tea leaves (green, black and white) all grown and processed in European tea gardens, and their vacuum-dried tea brews, prepared using both hot and cold water, to observe how the components differ from tea leaf to the in-cup infusion. Spectra were collected in the 1800–600 cm−1 region and were submitted to Principal Component Analysis (PCA). The comparison of the spectral profiles of leaves and hot and cold infusions of tea from the same country, emphasizes how they differ in relation to the different spectral regions. Differences were also noted among the different countries. Furthermore, the changes observed (e.g., at ~1340 cm−1) due to catechin content, confirm the antioxidant properties of these teas. Overall, this experimental approach could be relevant for rapid analysis of various tea types and could pave the way for the industrial discrimination of teas and of their health properties without the need of time-consuming, lab chemical assays.
Multinuclear complexes are metal compounds featured by adjacent bound metal centers that can lead to unconventional reactivity. Some M2L4-type paddlewheel dinuclear complexes with monoanionic bridging ligands feature promising properties, including therapeutic ones. Molybdenum has been studied for the formation of multiple-bonded M2+ compounds due to their unique scaffold, redox, and spectroscopic properties as well as for applications in several fields including catalysis and biology. These latter are much less explored and only sporadic studies have been carried out. Here, a series of four dimolybdenum (II,II) carboxylate paddlewheel complexes were synthesized using different Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) as ligands. The reaction of (NH4)5[Mo2Cl9]·H2O with the selected NSAIDs in methanol produced the complexes Mo2(μ-O2CR)4 where RCO2 is ibuprofen (1), naproxen (2), aspirin (3) and indomethacin (4). The products were obtained in good yields and extensively characterized with integrated techniques. Stability and solution behaviour were studied using a mixed experimental and computational approach. Finally, the biological activity of 1 and 3 (i.e. the most reactive and the most stable compounds of the series, respectively) was preliminarily assessed confirming the disassembling of the molecules in the biological milieu. Overall, some very interesting results emerged for these unconventional compounds from a mechanistic point of view.
Raman MicroSpectroscopy (RMS) is a powerful label-free tool to probe the effects of drugs at a cellular/subcellular level. It is important, however, to be able to extract relevant biochemical and kinetic spectroscopic signatures of the specific cellular responses. In the present study, a combination of Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS) and Principal Component Analysis (PCA) is used to analyse the RMS data for the example of exposure of primary Oral Squamous Carcinoma Cells (OSCC) to the chemotherapeutic agent cisplatin. Dosing regimens were established by cytotoxicity assays, and the effects of the drug on cellular spectral profiles were monitored from 16 to 72 hours post-exposure using an apoptosis assay, to establish the relative populations of viable (V), early (EA) and late apoptotic/dead (LA/D) cells after the drug treatment. Based on a kinetic model of the progression from V > EA > D, MCR-ALS regression analysis of the RMS responses was able to extract spectral profiles associated with each stage of the cellular responses, enabling a quantitative comparison of the response rates for the respective drug treatments. Moreover, PCA was used to compare the spectral profiles of the viable cells exposed to the drug. Spectral differences were highlighted in the early stages (16 hours exposure), indicative of the initial cellular response to the drug treatment, and also in the late stages (48-72 hours exposure), representing the cell death pathway. The study demonstrates that RMS coupled with multivariate analysis can be used to quantitatively monitor the progression of cellular responses to different drugs, towards future applications for label-free, in vitro, pre-clinical screening.
The presence of microplastics (MPs) in human fluids and organs is a great concern, since, as highlighted by recent studies on animal models, they could cause alterations of several physiological functions, including reproduction. In this study, semen samples collected from men living in a polluted area of the Campania Region (Southern Italy), were analyzed to assess the presence of MPs. N. 16 pigmented microplastic fragments (ranging from 2 to 6 μm in size) with spheric or irregular shapes were found in six out of ten samples. All the detected MPs were characterized in terms of morphology (size, colour, and shape) and chemical composition by Raman Microspectroscopy. Chemical composition showed the presence of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polystyrene (PS), polyvinylchloride (PVC), polycarbonate (PC), polyoxymethylene (POM) and acrylic, suggesting ingestion and/or inhalation as a route of exposure to environmental MPs. In this work, we propose for the first time a mechanism by which MPs pass into the semen most likely through the epididymis and seminal vesicles, which are the most susceptible to inflammation.
European countries have recently started experimenting with growing and producing their own teas in small quantities, mainly for the specialty tea sector. To characterize European teas, this study investigated a set of five tea types obtained from different Camellia sinensis varieties/cultivars, representing various oxidation grades (green, white, yellow, oolong, black), all grown and processed in the only tea garden in Europe (in Germany) that focuses on all five types. Hot and cold brews were studied by measuring the total phenolic (TPC) and flavonoid contents (TFC), the antioxidant capacity and UV-Vis spectra, also with the objective of discriminating between the different tea types and the different plant varieties. The dried leaves were analyzed to measure the content of essential and toxic elements and by ATR-FTIR spectroscopy to determine a chemical fingerprint for identifying the tea varieties and types. The average levels of TPC (hot brew = 5.82 ± 2.06; cold brew = 5.4 ± 2.46 mM GAEq), TFC (hot brew = 0.87 ± 0.309; cold brew = 0.87 ± 0.413 mM CAEq), and antioxidant capacity (ORAC assay-hot brew = 20.9 ± 605; cold brew = 21.8 ± 8.0 mM TXEq, ABTS assay-hot brew = 15.2 ± 5.09; cold brew = 15.1 ± 5.8 mM TXEq, FRAP assay-hot brew = 9.2 ± 3.84; cold brew = 10.4 ± 5.23 mM AAEq) observed compared well with those from other parts of the world such as China, Africa, and Taiwan. The hazard quotient <1 and the hazard index of 0.14 indicate that there is no non-carcinogenic risk from consumption of these teas. The obtained information is essential for elucidating the characteristics and the impact of tea processing and tea variety on the health benefits of these tea products coming from a single European tea garden. This multifaceted approach would help tea growers in Europe increase their knowledge on the health attributes of the teas they grow, ultimately leading to optimization of the nutraceutical properties of these teas.
Lyotropic Liquid Crystalline (LLC) nanoparticles represent an emerging class of smart, biocompatible, and biodegradable systems for the delivery of drugs. Among these, structures with complex 3D architectures such as cubosomes are of particular interest. These are non- lamellar assemblies having hydrophobic and hydrophilic portions able to carry drugs of different nature. They can further be modulated including suitable additives to control the release of the active payload, and to promote an active targeting. Starting from monoolein (GMO) cubic phase, different concentrations of mannose-based esters were added, and the eventual structural modifications were monitored to ascertain the effects of the presence of glycolipids. Moreover, the structural properties of these nanosystems loaded with Dexamethasone (DEX), a very well-known anti-inflammatory steroid, were also studied. Experiments were carried out by synchrotron Small Angle X-ray Scattering (SAXS), Raman Microspectroscopy (RMS) and Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) measurements. The drug delivery potential (i.e. entrapment efficiency and release properties) of the obtained nanoparticles was evaluated. Finally, in vitro cytocompatibility and anti-inflammatory activity studies of the prepared formulations were carried out. Inclusion of mannose-based surfactants up to 10 mol% influenced the structural parameters of Im3m cubic phase and swollen cubic phases were obtained with the different glycolipids with lattice parameters significantly higher than GMO. A complete cytocompatibility and an increased DEX activity were observed, thus suggesting the possibility to use GMO/glycolipids nanoparticles to formulate innovative drug delivery systems.
The Mediterranean Sea is particularly endangered by microplastics (MPs), polymers, and additives. These contaminants can be ingested by fishes and, hence, translocate into tissues. We aimed to quantify MPs, polyethylene terephthalate (PET), polycarbonate (PC), bisphenol A (BPA), and p-phthalic acid (PTA) in the edible muscles of swordfish (Xiphias gladius) and bluefin tuna (Thunnus thynnus) caught in the Mediterranean Sea. The MPs were extracted from muscles and characterized by stereomicroscopy and Raman microspectroscopy, while the polymers (PET and PC) and additives (BPA and PTA) were identified by LC-MS/MS. The number of MPs ranged from 140 to 270 no. kg−1 in swordfish and from 160 to 270 no. kg−1 in tuna. The most frequent MP polymer was polypropylene in swordfish (33%) and in tuna (34.7%), while the most abundant pigments were PB115, PB116, PBr101/102. A similar level of plastic contamination was revealed in these two fish species with differences in shapes, colors, pigments and polymers of MPs.