Introduction: The ingredients from the dental restoratives are known to leach and elicit a host response. The prerequisite to deem a material biocompatible requires its toxicologic evaluation. The study was performed to analyze the probable toxicity resulting from silorane-based composite (SBC) with methacrylate-based composite (MBC). Materials and Methods: The in vitro cytotoxicity test, methyl thiazolyl tetrazolium (MTT) assay, evaluated the cell viability and proliferation rate of dental pulp cells (DPCs). The extirpated pulp was cultured in α-MEM-containing supplements and incubated at 37°C. DPCs were subjected to varying doses of SBC or MBC at different time intervals after attaining confluence and monitored for proliferation and viability via MTT assay. An independent Student t test was performed to compare the effect of composites on the DPC. The cytotoxicity levels were compared using one-way analysis of variance and posthoc Tukey multiple comparison test at 5% level of significance and P-value of <0.05. Results: DPC exposed to MBC showed higher viability than SBC. The MTT assay reported the number of viable cells as (>90%) in the first 24 hours. The count significantly reduced by the end of 48 hours (minimum 65% in 25 μg/ml) at all concentrations (P < 0.05). SBC had lower survival than MBC in all concentrations and periods. Except at 5 μg/ml concentration at 48 hours in SBC, no statistically significant values were reported. Conclusion: DPCs are prone to the cytotoxicity caused by dental composite. In contrast to MBC, the cytotoxicity of SBC declines overtime.

Background: Caesalpinia bonduc (CB) is said to own various pharmacological and therapeutic application against a number of diseases. It is used widely in folk medicine to treat liver diseases. In the present study, we have made a sincere effort to evaluate the hepatoprotective activity of CB leaf extracts against Paracetamol (PCM) induced toxicity and their mechanism of hepatoprotection in the human Hepatocarcinoma cells (HepG2 cells) thereby providing scientific evidence for the same. Material and Methods: The hepatoprotective activity of CB was assessed in-vitro by the estimation of glutathione (GSH) and Malondialdehyde (MDA), anti-apoptotic assay/Annexin V and the expressions of genes such as Glutathione Reductase (GS-R) and Glutamate-Cysteine Ligase, Catalytic (GCLC). Results: The obtained results suggest that the aqueous extract of CB possess significant hepatoprotective activity. This activity may be due to the possible antioxidant property and the free radical scavenging ability of the extracts, which might clear the toxic metabolites of PCM. Conclusion: The present study suggests that the aqueous extract of CB have potential hepatoprotective activity, which may prevent the lipid peroxidation of the cell membrane by its antioxidant properties.

Natural medicinal systems such as Ayurveda and folk medicine has remedies for wound management. However, the exact cellular and extracellular mechanisms involved in the healing process and its influence on keratinocytes is less discussed. Therefore, the present study was designed to evaluate the effect of certain natural wound healing medicines on the biology of the keratinocytes/HaCaT cells. Test materials such as honey (H), ghee (G), aqueous extracts of roots of Glycyrrhiza glabra (GG) and leaves of Nerium indicum (NI) were considered. The HaCaT cells were treated with the test materials singly and in combinations (H+G, all combined [Tot]) for a specific period (24, 48, and 72 hours). The cells were then subjected to cytotoxicity/proliferation and migration/scratch assays. All the test materials, except NI, were non-cytotoxic and showed increased cell proliferation at variable concentrations. Significant observations were made in the groups treated with honey (100 µg/ml at 48 hours, P<0.05; 1,000 µg/ml at 72 hours, P<0.05), GG (all concentrations at 48 hours, P<0.05; 750 µg/ml at 72 hours, P<0.05), H+G (250 µg/ml at 24 hours, P<0.001; 500 µg/ml at 48 and 72 hours, P<0.05), and Tot (50 µg/ml at 24, 48 and 72 hours, P<0.01). In the in-vitro wound healing assay, all the treated groups showed significant migration and narrowing of the scratch area by 24 and 48 hours (P<0.001) compared to control. The results obtained from the present study signifies the positive influence of these natural wound healing compounds on keratinocytes/HaCaT cells.

Background Traditional medicinal systems like Ayurveda and Indian folk medicine have used Honey, Ghee, Glycyrrhiza glabra, and Nerium indicum effectively for treating wounds. The known result of these medications is faster healing. However, the mechanism of actions at the tissue level, the biochemical and molecular mechanisms of healing is not well explored and documented. This present study was therefore designed to study the efficacy of these traditional medicines singly and in combinations on excision wounds in Wistar rats. Methods At two different intervals (i.e., day 8 and day 16), biomechanical, histological and immunohistochemical (IHC) parameters were assessed at the wound site. IHC focused on the inflammatory rate by evaluating the level of cytokine, IL1β and the tissue remodeling by studying the activity of myofibroblasts. Results Rapid epithelization, better remodeling, favorable inflammatory changes and an adequate myofibroblast activity at the wound site was observed in all the treated groups compared to control. Conclusion This study is therefore useful in exploring the mechanism of action of these traditional medicines and providing valuable scientific evidence.

Natural medicinal systems like Ayurveda, has remedies for wound treatment and management. However the exact cellular and extracellular mechanisms involved in the healing process and its influence on fibroblasts is seldom known. This is important because fibroblast is one of the major entities which play a significant role in wound healing. Therefore the present study was designed to evaluate the effect of some natural wound healing medicines used in Ayurveda on the biology of the dermal fibroblast. Test materials such as honey, ghee, aqueous extracts of roots of Glycyrrhiza glabra and leaves of Nerium indicum, were obtained as per the standard protocol. The dermal fibroblasts obtained from rat skin samples were treated with test materials singly or in combinations for a specific period of time in the culture. After the treatment period, cells were subjected to cytotoxicity/proliferation assay, migration/scratch assay and finally the RNA was isolated from them and expression level of FGF2 was evaluated by RT-PCR. All the test materials except Nerium indicum were non cytotoxic and showed increased cell proliferation rate in comparison with the untreated cells. Nerium indicum on the contrary was cytotoxic to the dermal fibroblasts in all the doses calculated. In the in vitro wound healing assay, the test materials had no influence on the migration of the fibroblasts. Further, the Nerium indicum showed maximum inhibition for migration of fibroblasts across the scratch. But the expression of FGF2 was higher in all the tested groups compared to the untreated cells. The preliminary results obtained from the present study indicate the influence of these natural wound healing compounds on fibroblasts. Further evaluation is required to understand the intricate cellular and molecular mechanism of these test materials which may help us to design the appropriate combination of test materials in s challenging wounds.

Fibroblasts produce many types of extracellular matrix (ECM) in skin such as collagen, laminin, elastin etc. Though melanocytes are not directly in contact with fibroblasts in skin, ECM components from fibroblasts are found to have significant impact on melanocyte biology. In vitiligo, it is known that melanocytes are either absent or dysfunctional. As one of the treatments strategy, non-lesional skin punches or isolated melanocytes are often auto grafted to the lesional skin. But the outcome is often unsatisfactory due to known or unknown reasons. Altered microenvironment at the lesioned site could be one of the reasons which inhibit the survival and function of melanocytes. Present study is designed to evaluate the influence of ECM produced by fibroblasts isolated from the normal and vitiligo skin on survival and function of normal melanocytes. After obtaining the institutional ethical committee approval, fibroblasts were isolated from the foreskin from children, healthy adult's skin, nonlesional skin and lesional skin of vitiligo patients. Melanocytes were isolated from foreskin from children. ECM layers were prepared from confluent monolayers of fibroblasts of different origin. Melanocytes were cultured on these ECM layers and melanin content, tyrosinase content and activity, melanocyte survival and apoptosis were analyzed. Lower survival rate, increased tyrosinase content, increased melanin content and increased apoptosis was observed in melanocytes grown on ECM derived from vitiligo lesional skin compared to the melanocytes grown on ECM derived from other sources of skin. This preliminary in vitro study showed that ECM components produced by fibroblasts isolated from lesional skin of the vitiligo patients creates the unfavorable microenvironment to the melanocyte survival and function. Further, studies involving more number of samples and clinical would reveal further details which may help in designing more efficient treatment strategies to treat the vitiligo.

INTRODUCTION:Melanocyte culture is an integral part of the studies of skin biology and cosmetic applications. After the introduction of selective medium for the culture of human melanocyte using Phorbol 12-myristate13-acetate (PMA) in 1982, a lot of methods of culturing were tried but till date PMA is a preferred mitogen because of its cost effectiveness compared to growth factors. We have tried to preliminarily evaluate the efficacy of another phorbol ester, Phorbol 12, 13-dibutyrate (PDBu) in melanocyte culture because of its less hydrophobic nature compared to PMA. This property minimizes the trace amount of mitogen in cell culture after washing off and hence does not interfere in other biological assays.AIM:To evaluate the differences in the melanocyte survival rate, morphology and mitotic index when grown in media supplemented with PMA and PDBu.MATERIALS AND METHODS:Foreskins were collected from children undergoing circumcision. Epidermal cells were isolated from foreskin and cultured using PMA and PDBu. Melanocytes in culture were monitored for the better establishment and documented. In proliferative assay, melanocytes were treated with PMA and PDBu for 24, 48 and 72 hours and proliferation was measured using 3-(4,5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay method.RESULTS:When cultured, melanocytes acquired proliferative status and bipolar morphology quicker in PDBu medium than in PMA medium. Keratinocytes survived as contamination in PMA medium whereas PDBu medium had minimal keratinocytes. MTT assay showed that PDBu has higher proliferative induction capacity than PMA. In even lower concentration of PDBu in medium, melanocytes survived till 72 hours without significant cell loss in compared to PMA medium.CONCLUSION:PDBu can be a valuable replacement for PMA in human melanocyte culture. Higher proliferation induction, unfavourable to keratinocyte survival and less hydrophobicity make PDBu a promising alternative for quicker establishment of pure human melanocyte cultures especially in cosmetic in vitro experimental dermatology.

AIM:The effects of leached substances from the restorative dental materials may induce local and systemic adverse effects. Thus the biological and toxic properties of the restorative dental materials must be compatible with the oral tissues or with general health. Therefore, the need for biocompatible restorative dental material implies the necessity of toxicity testing. It was the purpose of this investigation to determine and compare the possible toxic effect of silorane based composite (Filtek P90) on human gingival fibroblast (HGF) in vitro using cytotoxicity measuring parameters (MTT assay) in comparison with its methacrylate counterpart (Z100) for their viability, proliferation rate.MATERIALS AND METHODS:Fresh healthy biopsy specimens of human gingival tissue of patients were obtained. For HGF, cells were cultured in Dulbecco's modified Eagle medium and grown to sub confluent monolayers. After attaining confluence, cells were treated with different doses of the Filtek P90 or Z 100 for different time point. HGF cells were observed for their proliferation, viability by MTT assay.RESULTS:The results of the cytotoxicity assay showed that, the percentage of viable cells was very good in the first 24h and marginally decreased in the next 48h period in all groups. However, the proliferation rate was never below 84% in all the groups, at any given concentration. Filtek P90 and Z100 treated cells exhibited insignificant decrease in the cell proliferation both in 24h and 48h exposure when compared to significant decrease in the cell survival rate in the positive control (Mitomycin C 250 μg/ml).) Comparison of the toxicity between Filtek P90 and Z100 in 24h & 48h separately showed that there was no significant difference (p<0.05) between these two composites in 24h and 48h' time period at all concentrations of the composites.CONCLUSION:To conclude, the new silorane based restorative composite showed comparable cytotoxic characteristics to clinically successful dimethacrylate composites suggesting the non-toxic nature in the oral environment and hence contributing to clinical success of these new restorative materials.

The process of melanogenesis in melanocytes and the transport of melanin in the form of melanosomes to the neighboring keratinocytes are the key steps in human skin pigmentation. Keratinocytes and melanocytes interact in intricate manner to maintain the homeostasis. The present study was designed to understand the role of cell-cell interaction through the gap junctions between melanocytes and keratinocytes on melanogenesis. We show that, inhibition of the gap junctional activity between human keratinocytes and melanocytes in a coculture system using gap junction blocker lowers the expression of key regulatory genes of melanogenesis such as tyrosinase and microphthalmiaassociated transcription factor (MITF). This was followed by concurrent decrease in tyrosinase protein levels and activity. Our results show the preliminary evidence for the regulation of melanogenesis in melanocytes through direct gap junctional communication by keratinocytes. Deciphering the mechanism and factors involved in the process would uncover the significance of gap junctions in melanogenesis.