Journal of the European Academy of Dermatology and VenereologyEarly View Letter to the Editor TRPM8 agonist (cryosim-1) gel for scalp itch: a randomised, vehicle-controlled clinical trial S.Y. Kang, S.Y. Kang orcid.org/0000-0001-6532-2244 Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaThese authors contributed equally to this work.Search for more papers by this authorM.G. Choi, M.G. Choi Department of Computer Science and Engineering, Kwangwoon University, Seoul, KoreaThese authors contributed equally to this work.Search for more papers by this authorE.T. Wei, E.T. Wei School of Public Health, University of California, Berkeley, CA, USASearch for more papers by this authorT. Selescu, T. Selescu Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucuresti, RomaniaSearch for more papers by this authorS.Y. Lee, S.Y. Lee Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorJ.C. Kim, J.C. Kim orcid.org/0000-0001-5846-0008 Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorB.Y. Chung, B.Y. Chung Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorC.W. Park, C.W. Park Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorH.O. Kim, Corresponding Author H.O. Kim hyeonekim@gmail.com Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, Korea Correspondence: H.O. Kim. E-mail: hyeonekim@gmail.comSearch for more papers by this author S.Y. Kang, S.Y. Kang orcid.org/0000-0001-6532-2244 Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaThese authors contributed equally to this work.Search for more papers by this authorM.G. Choi, M.G. Choi Department of Computer Science and Engineering, Kwangwoon University, Seoul, KoreaThese authors contributed equally to this work.Search for more papers by this authorE.T. Wei, E.T. Wei School of Public Health, University of California, Berkeley, CA, USASearch for more papers by this authorT. Selescu, T. Selescu Department of Anatomy, Physiology and Biophysics, Faculty of Biology, University of Bucharest, Bucuresti, RomaniaSearch for more papers by this authorS.Y. Lee, S.Y. Lee Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorJ.C. Kim, J.C. Kim orcid.org/0000-0001-5846-0008 Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorB.Y. Chung, B.Y. Chung Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorC.W. Park, C.W. Park Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, KoreaSearch for more papers by this authorH.O. Kim, Corresponding Author H.O. Kim hyeonekim@gmail.com Department of Dermatology, Kangnam Sacred Heart Hospital, Hallym University, Seoul, Korea Correspondence: H.O. Kim. E-mail: hyeonekim@gmail.comSearch for more papers by this author First published: 16 March 2022 https://doi.org/10.1111/jdv.18080 Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Open Research Data availability statement Data are openly available in a public repository that issues datasets with DOIs. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation

While the enormous clinical and psychosocial importance of pruritus in many areas of medicine and the detrimental effects of chronic 'itch' on the quality of life of an affected individual are widely appreciated, the complexity of this sensation is still often grossly underestimated. The current Controversies feature highlights this complexity by portraying pruritus as a truly interdisciplinary problem at the crossroads of neurophysiology, neuroimmunology, neuropharmacology, protease research, internal medicine, and dermatology, which is combated most successfully if one keeps the multilayered nature of 'itch' in mind and adopts a holistic treatment approach - beyond the customary, frequently frustrane monotherapy with histamine receptor antagonists. In view of the often unsatisfactory, unidimensional, and altogether rather crude standard instruments for pruritus management that we still tend to use in clinical practice today, an interdisciplinary team of pruritus experts here critically examines recent progress in pruritus research that future itch management must take into consideration. Focusing on new insights into the neuroimmunological, neuroendocrine, and neurophysiological bases of pruritus, and discussing available neuropharmacological tools, specific research avenues are highlighted, whose pursuit promises to lead to novel, and hopefully more effective, forms of pruritus management.

CRH cutaneous expression is significantly enhanced after exposure to various stimuli (Physiol Rev 2000, 80;979–1020). We evaluated the effect of CRH on cytokine production in HaCaT keratinocytes, a cell line shown to express CRH receptors coupled to cAMP activation and calcium-dependent transmission pathways. It is demonstrated for the first time that exogenously added CRH stimulates production of IL-6 and IL-11. It also inhibits production of IL-1beta and does not affect TNF-alpha production. Our results indicate that CRH function(s) during cutaneous stress may be mediated by differential effects on cytokine production.

BACKGROUND:Observations that epidermal cells release both corticotropin-releasing hormone (CRH) and proopiome lanocortin (POMC) peptides has raised questions about the physiological relevance of this hypothalamo-pituitary-like system in mammalian skin. As CRH has shown anti-proliferative effects on cultured keratinocytes, we tested whether CRH can also regulate growth of melanoma cells.MATERIALS AND METHODS:CRH, [D-Glu20]-CRH, [D-Pro5]-CRH, acetyl-cyclo(30-33)[D-Phe12,D-Glu20,Nle21,D-His32,Lys33,D-Nle38]-CRH(4-41), acetyl-cyclo(30-33)[D-Phe12,Nle18,D-Glu20,Nle21,D-Ala32]-urotensin I(4-41), urocortin, and sauvagine were tested on Cloudman melanoma cell proliferation in culture and B16 melanoma tumor growth in C57B1/6 mice. Calcium-sensitive fluorescence measurements were used to examine the effect of CRH on intracellular Ca2+ signaling. The effects of CRH and [D-Glu20]-CRH on blood pressure were compared by measuring mean arterial pressure in anesthetized rats.RESULTS:CRH and six analogs were tested, and all demonstrated exceptional potency in inhibiting Cloudman cell proliferation in culture, with half-maximal effective concentrations ranging between 0.2 and 100 pM. The amplitude of ionomycin-induced Ca2+ influx into Cloudman cells grown in suspension was reduced by 50% after 48-hr exposure to CRH. Daily injections of CRH or [D-Glu20]-CRH, 100 micrograms/kg.day s.c., for 5 days, reduced net B16 tumor volume in mice by 30-60% compared to control animals. [D-Glu20]-CRH was less hypotensive compared to CRH, despite having similar anti-proliferative potency.CONCLUSION:CRH, and various analogs thereof, inhibit proliferation of Cloudman cells in culture, and inhibit B16 tumor growth rate in vivo, most likely by activation of endogenous CRH1 receptors and subsequent altered intracellular Ca2+ signaling. CRH analogs, such as [D-Glu20]-CRH, with less hypotensive activity may provide new directions of therapy for melanoma.

Studies in mammalian skin have shown expression of the genes for corticotropin-releasing hormone (CRH) and the related urocortin peptide, with subsequent production of the respective peptides. Recent molecular and biochemical analyses have further revealed the presence of CRH receptors (CRH-Rs). These CRH-Rs are functional, responding to CRH and urocortin peptides (exogenous or produced locally) through activation of receptor(s)-mediated pathways to modify skin cell phenotype. Thus, when taken together with the previous findings of cutaneous expression of POMC and its receptors, these observations extend the range of regulatory elements of the hypothalamic-pituitary-adrenal axis expressed in mammalian skin. Overall, the cutaneous CRH/POMC expression is highly reactive to common stressors such as immune cytokines, ultraviolet radiation, cutaneous pathology, or even the physiological changes associated with the hair cycle phase. Therefore, similar to its central analog, the local expression and action of CRH/POMC elements appear to be highly organized and entrained, representing general mechanism of cutaneous response to stressful stimuli. In such a CRH/POMC system, the CRH-Rs may be a central element.

Human neutrophils in whole blood become bipolar in shape after exposure to chemokinetic stimuli. In normal blood, the proportion of non-spherical neutrophils was 1.2±0.07% (n=101). After incubation of blood samples with corticotropin-releasing hormone (CRF, 1 to 20 μM) 36 of 101 subjects exhibited a ≥10% bipolar-shape ellipsoid response. This ellipsoid response was more frequent in female than in male subjects (32/75 vs. 4/26, p<0.01). Female Caucasian subjects were more sensitive to CRF than female East Asian subjects (25/48 vs. 2/15, p<0.01). Age was not a factor in sensitivity to CRF. In young female East Asian subjects (23±0.4 years, n=8) that did not manifest the ellipsoid response to CRF, formyl-Met-Leu-Phe (fMLP), a chemotactic peptide, 10−9 M increased non-spherical neutrophils to 31±0.8%. In these individuals, the fMLP response was inhibited in a dose-dependent manner by CRF. The pharmacological profile of the stimulatory and fMLP-inhibitory actions of CRF on neutrophil shape was consistent with that of a CRF1-receptor mediated response. Expression of mRNA for the CRF1-receptor was detected in hematopoietic cell lines (e.g., HL-60) using a reverse transcriptase polymerase chain-reaction method. The bipolar-shape response of human neutrophils to CRF has the potential to be a useful indicator of the functional state of this hormone-receptor system in inflammation.

Dynorphin A (Dyn A) is a 17-residue opioid peptide derived from prodynorphin precursors found in mammalian tissues. Removal of Tyr1 from Dyn A produces a peptide that is more potent than Dyn A in attenuating the acute phase of the inflammatory response, as measured by inhibition of heat-induced edema in the anesthetized rat’s paw (exposure to 58°C water for 1 min). Dyn A(2–17), however, no longer interacts with opioid receptors. It was postulated that the non-opioid anti-inflammatory actions of Dyn A(2-17) may reside in Dyn A(6-12); that is, Arg-Arg-Ile-Arg-Pro-Lys-Leu. here we report on the activities of Dyn A(6-12) analogs modified by substitutions on the N terminus, by single N-methyl substitution and by single replacement of residues by alanine. The results indicated that the minimal sequence required for an anti-edema ED50 of <1.0 μmol/kg IV was anisoyl-Arg6-Arg7-Xaa8-Arg9-Pro10-Xaa11-Xaa12-NH2. A prototype, p-anisoyl-[d-Leu12] Dyn A(6-12)-NH2, with an ED50 of 0.20 μmol/kg IV compared to an ED50 of 0.08 μmol/kg IV for Dyn A(2-17), was selected for further tests of biological activity. This analog, like Dyn A(2-17), lowered blood pressure in anesthetized rats. In a model of neurogenic inflammation, produced by antidromic stimulation of the vagus in the anesthetized rat, p-anisoyl-[d-Leu12] Dyn A(6–12)-NH2, 0.23 μmol/kg IV, attenuated the negativity of tracheal tissue interstitial pressure (Pif), which normally develops after nerve stimulation. Modulation of interstitial pressure may be the mechanistic basis for the anti-edema properties of these Dyn A(6-12) analogs.

The activities of corticotropin-releasing hormone (CRH)-related peptides and several analogs were examined in cells transfected with either CRH1 or CRH2beta receptors, in suppression of heat-induced rat paw edema in pentobarbital-anesthetised animals and in stimulation of release of immunoreactive corticotropin (ir-ACTH) from rat anterior pituitary tissue in vitro. The peptides tested were human/rat (h/r)-CRH, r-urocortin, h-urocortin, white sucker fish or maggy sole urotensin I and some analogs of these peptides substituted with D-amino acids at residues 4 (urocortin), 5 (CRH and urotensin I) and 20 (CRH). In cells transfected with CRH1 receptors, these peptides were similar in potency in stimulation of cAMP accumulation. By contrast, at CRH2beta receptors peptides of the urocortin and urotensin series were more potent than h/r-CRH while [D-Glu20]-h/r-CRH was 6.5-fold less active than h/r-CRH. I.v. administration of h/r-CRH or related peptides 10 min prior to a thermal stimulus produced a significant dose-dependent inhibition of rat paw edema formation. Comparison of the ED50's showed that urocortins ([D-Ser4]-h-urocortin, h-urocortin, [D-Pro4]-r-urocortin, r-urocortin) were approximately 2 to 3 times more active than h/r-CRH, but [D-Glu20]-h/r-CRH was 18.5-fold less active. In the assay for ir-ACTH release, the activity of h/r-CRH and [D-Glu20]-h/r-CRH was similar but [D-Pro5]-h/r-CRH and [D-Pro4]-r-urocortin was less potent than the native peptide. These results provide further evidence that D-amino acid substitution at residue 20 reduces the potency of h/r-CRH at endogenous (anti-edema effect) and transfected (cAMP accumulation) CRH2beta receptors whilst activity at the CRH1 receptor is retained (ACTH-release and cAMP accumulation). On the other hand substitutions at residues 4 or 5 in r-urocortin or h/r-CRH respectively appear to decrease activity at CRH1 but not CRH2beta receptors The modified CRH and urocortin analogs described here may provide clues for the further design of receptor selective ligands.

Corticotropin releasing factor (CRF) induces a rapid, within seconds, and dose‐dependent increase in the intracellular Ca2+ in both human and hamster melanoma cells. This effect is inhibited by depletion of extracellular calcium using 3 mM EGTA and is attenuated by the CRF receptor antagonist, α‐helical‐CRF(9‐41). Other peptides of the CRF superfamily, sauvagine and urocortin, also induce increases in cytoplasmic calcium concentration but at higher concentrations than CRF. We conclude that malignant melanocytes express CRF receptors, which are coupled to activation of plasma membrane calcium channels.

Mystixins are synthetic peptides that inhibit plasma leakage after tissue injury. We sought to determine the mechanism of the antileakage effect of mystixins, with particular reference to the formation of endothelial gaps in postcapillary venules. Intravenous administration of mystixin-7, a prototype heptapeptide (p-anisoyl-Arg-Lys-Leu-Leu-D-Thi-Ile-D-Leu-NH2), decreased Evans blue leakage induced by substance P (5 microg/kg i.v.) with an ED50 (95% confidence limits) of 130 (76-211) microg/kg in trachea and 52 (27-100) microg/kg in skin of anesthetized F344 rats. Leakage was decreased without a reduction in the number or size of endothelial gaps, visualized by silver deposits after silver nitrate staining. The number of silver deposits per tracheal endothelial cell was 11.4 +/- 0.2 (mean +/- S.E.) after vehicle pretreatment vs. 13.0 +/- 0.8 after mystixin-7 pretreatment (100 microg/kg i.v.). Silver deposit diameter was unchanged at 1.4 +/- 0.1 micron. Mean arterial blood pressure dropped by a maximum of 38% from baseline for approximately 10 min after mystixin-7 (100 microg/kg i.v.), then recovered to a plateau at about 13% below baseline. The antileakage effect of mystixin-7 pretreatment in vivo was also demonstrated in aldehyde-fixed vessels perfused in situ with Evans blue at constant flow (skin, 79% reduction; trachea, 49% reduction), which suggests that mystixin can reduce leakage independent of its hypotensive effect. We conclude that the antileakage effect of mystixin does not depend on reducing the number or size of endothelial gaps, but instead could be caused by residual hypotension, which reduces the negative interstitial fluid pressure toward zero, or clogging of endothelial gaps.

In addition to the well-established effects of corticotrophin-releasing factor (CRF) synthesized in the hypothalamic paraventricular nucleus in modulating the stress response, CRF has also been implicated in a number of other functions. In particular both pro- and anti-inflammatory effects have been proposed for CRF. In the present study we have investigated the effects of 14 day peripheral infusion of CRF on the development of adjuvant-induced arthritis (AA) in the rat. To avoid confounding effects of the CRF stimulating endogenous corticosterone, all animals in the study were adrenalectomized. We were unable to determine any effect of the treatment at either of the doses of CRF investigated. The bioactivity of the CRF was confirmed in vitro and the presence of substantial circulating levels of CRF in plasma in the high dose group at time of sacrifice suggest that the CRF was successfully infused over the 14 day experimental period. These data suggest that CRF is not important in the mediation of AA. Alternatively either intact adrenal glands may be required for the action of CRF to become apparent or locally produced endogenous CRF may have more subtle effects than chronic infusion of synthetic CRF.

In an earlier study, dynorphin A(1-13) [Dyn A(1-13)] was shown to inhibit heat-induced edema in the anesthetized rat's paw but the potency of this action was low, with effective doses in the range of 3-4 mg/kg i.v. In this study, Dyn A and related fragments were tested. Thermal edema was elicited in anesthetized male albino rats by immersion of the hindpaw in 58 degrees C water for 1 min. The median effective dose (ED50 and 95% confidence limits) in mg/kg i.v. for inhibition of edema were: Dyn A, Dyn A(2-17), and Dyn A(1-13), 1.7 (1.2-2.4), 0.15 (0.09-0.24), and 3.2 (1.9-5.5), respectively. The ED50 values of [D-Ala2]Dyn A, [D-Ala2]Dyn A(2-17), and [D-Ala2]Dyn A(2-17)-amide were found to be 0.92 (0.40-2.10), 1.25 (0.60-2.63), and 0.65 (0.36-1.16) mg/kg i.v., respectively. Dyn A(2-17), 0.5 mg/kg i.v., also inhibited pulmonary edema produced by i.v. injection of epinephrine. The anti-edema action of Dyn A(2-17) was not blocked by naloxone, an opioid receptor antagonist, or dependent on the hypotensive action of this peptide. It is postulated that the antiedema activity of Dyn A resides in the core fragment Dyn A(6-12). Two peptides, N-acetyl-Dyn A(6-12)-amide and N-acetyl-[D-Leu12]Dyn A(6-12)-amide, were synthesized and, when tested, were effective in reducing thermal edema with ED50 values of 1.4 (0.6-3.7) and 2.2 (1.2-4.1) mg/kg i.v., respectively.

Peptides of the neurotensin (NT) and xenopsin (XP) families inhibit vascular leakage in various models of tissue injury. In this study, we measured the potency of NT fragments, NT analogs and NT-(8-13) analogs for inhibition of thermal edema induced by immersion of the anesthetized rat's paw in 58 degrees C water for 1 min. The pattern of anti-edema potencies seen with sixteen NT-(8-13) analogs correlated well with the pattern of activities obtained in binding measurements to rat brain membrane preparations and to activities in isolated organ preparations. Replacement of Tyr(11) with Trp in NT-(8-13) and Arg(8) with D-Arg resulted in an analog [D-Arg(8), Trp(11)]NT-(8-13) which was 5-times more potent than NT-(8-13). Substitution of D-Arg for Arg(8) and Arg(9) in NT-(8-13) produced analogs that retained anti-edema activity but with decreased effects on gut motility and hypotension.

Substance P (SP) administered 40 μg/kg s.c. to pentobarbital-anesthetized rats induced salivation and leakage of plasma constituents into the skin, muscle, trachea, esophagus and bladder, as measured by Monastral blue B labeling of small blood vessels or by extravasation of Evans blue dye into tissues. These SP effects were inhibited by N-acetyl-neurotensin-(8–13) (Ac-NT-(8–13)) and by CP-96,345, a nonpeptide SP receptor antagonist. Intralumenal injection of Ac-NT-(8–13) or CP-96,345 into the bladder reduced SP-induced leakage of Evans blue dye but not dye leakage into the pawskin, indicating a localised drug action. Ac-NT-(8–13) appears to act directly on discrete sites in skin and in mucous membranes to functionally antagonize the inflammatory effects of SP.

Thirty-three ovine corticotropin-releasing factor (CRF) analogs, systematically substituted with alanine (Ala) residues, were tested for inhibitory activity on edema induced in the pentobarbital-anesthetized rat paw by heat (immersion in 58 degrees C water for 1 min). The activity of each analog, administered 0.1 mg/kg i.v. 10 min before heat, was compared to the rank order of the analog's potency in stimulating adrenocorticotropin (ACTH) release from cultured rat pituicytes. A strong positive rank correlation was found between the anti-edema and neuroendocrine activities of these analogs.

In various animal models of tissue injury, corticotropin-releasing factor (CRF) and related peptides inhibit swelling, edema and loss of protein from the vascular compartment. To search for smaller peptide segments of CRF that might retain anti-inflammatory activity, the authors tested peptides similar to the carboxy terminals of ovine (o) and human/rat (h/r) CRF. Also, because h/rCRF(35-39), -Arg-Lys-Leu-Met-Glu-, resembles Arg-Lys-Leu-Leu-Glu-, a sequence found in many intermediate filament proteins, analogous peptides were evaluated. Ovine CRF(21-41), -Met-Thr-Lys-Ala-Asp-Gln-Leu-Ala-Gln-Gln-Ala-His-Ser-Asn-Arg-Lys- Leu-Asp-Ile-Ala-NH2, its carboxy terminal carboxyl derivative, oCRF(21-41)-OH, and the fragments, oCRF(26-41) and oCRF(30-41), were inactive when assayed at 5 mg/kg i.v. on edema induced in the pentobarbital-anesthetized rat's hindpaw after immersion in 58 degrees C water for 1 min. Crude peptides, D-Leu-Ala-Thr-D-Tyr-Arg-Lys-Leu-Leu-Glu-Ile-D-Leu-NH2 and D-Ala-His-Ser-D-Asn-Arg-Lys-Leu-Leu-Glu-Ile-D-Leu-NH2, were found to have activity in this bioassay. Characterization of the structures within the crude mixture revealed that substitution of the glutamic acid residue with an anisolyated glutamic acid (2-amino-5-(methoxyphenyl)-5-oxopentanoic acid) derivative, designated as (A*), increased the overall potency. The glutamyl-anisole derivative was a by-product of the temperature-dependent Friedel-Crafts acylation reaction that occurs during hydrogen fluoride cleavage of glutamyl-containing peptides.(ABSTRACT TRUNCATED AT 250 WORDS)