PMID: 

Nat Rev Immunol. 2008 Sep ;8(9):685-98. PMID: 19172691

Abstract Title: 

Vitamin effects on the immune system: vitamins A and D take centre stage.

Abstract: 

Vitamins are essential constituents of our diet that have long been known to influence the immune system. Vitamins A and D have received particular attention in recent years as these vitamins have been shown to have an unexpected and crucial effect on the immune response. We present and discuss our current understanding of the essential roles of vitamins in modulating a broad range of immune processes, such as lymphocyte activation and proliferation, T-helper-cell differentiation, tissue-specific lymphocyte homing, the production of specific antibody isotypes and regulation of the immune response. Finally, we discuss the clinical potential of vitamin A and D metabolites for modulating tissue-specific immune responses and for preventing and/or treating inflammation and autoimmunity.

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PMID: 

Vitam Horm. 2011 ;86:23-62. PMID: 21419266

Abstract Title: 

Vitamin D and innate and adaptive immunity.

Abstract: 

In the last 5 years there has been renewed interest in the health benefits of vitamin D. A central feature of this revival has been new information concerning the nonclassical effects of vitamin D. In particular, studies of the interaction between vitamin D and the immune system have highlighted the importance of localized conversion of precursor 25-hydroxyvitamin D (25OHD) to active 1,25-dihydroxyvitamin D (1,25(OH)(2)D) as a mechanism for maintaining antibacterial activity in humans. The clinical relevance of this has been endorsed by increasing evidence of suboptimal 25OHD status in populations across the globe. Collectively these observations support the hypothesis that vitamin D insufficiency may lead to dysregulation of human immune responses and may therefore be an underlying cause of infectious disease and immune disorders. The current review describes the key mechanisms associated with vitamin D metabolism and signaling for both innate immune (antimicrobial activity and antigen presentation) and adaptive immune (T and B lymphocyte function) responses. These include coordinated actions of the vitamin D-activating enzyme, 1α-hydroxylase (CYP27B1), and the vitamin D receptor (VDR) in mediating intracrine and paracrine actions of vitamin D. Finally, the review will consider the role of immunomodulatory vitamin D in human health, with specific emphasis on infectious and autoimmune disease.

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PMID: 

Environ Sci Pollut Res Int. 2020 Mar 31. Epub 2020 Mar 31. PMID: 32232762

Abstract Title: 

Geraniol attenuates oxidative stress, bioaccumulation, serological and histopathological changes during aluminum chloride-hepatopancreatic toxicity in male Wistar rats.

Abstract: 

Aluminum chloride (AlCl) has different industrial applications including manufacturing paint and water treatment. The present study was designed to evaluate the alleviating effect of geraniol against AlCl-induced hepatopancreatic toxicity. To this end, forty male Wistar rats were divided into control (0.9% NaCl, IP), geraniol (100 mg/kg orally), AlCl(70 mg/kg, IP), and AlCl(70 mg/kg, IP) plus geraniol (100 mg/kg orally) groups and then were treated daily for 28 days. Based on the results, serum cholesterol, triglyceride, as well as liver and pancreas enzymes increased significantly (P 

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PMID: 

Am J Clin Nutr. 2004 Mar ;79(3):444-50. PMID: 14985220

Abstract Title: 

Effect of zinc supplementation on immune and inflammatory responses in pediatric patients with shigellosis.

Abstract: 

BACKGROUND: Several studies showed benefits of long-term zinc supplementation on the incidence, severity, and duration of diarrhea and on the incidence of respiratory infections. Prolonged zinc supplementation also improves cell-mediated immunity in severely malnourished children.OBJECTIVE: We studied the effect of short-term zinc supplementation on intrinsic and specific immune and inflammatory responses in moderately malnourished children with acute shigellosis.DESIGN: A randomized, double-blind, placebo-controlled trial was conducted in Shigella-infected children aged 12-59 mo. Elemental zinc (20 mg) and a multivitamin containing vitamins A and D, thiamine, riboflavin, nicotinamide, and calcium at twice the recommended dietary allowance were given daily for 2 wk to the zinc group (n = 28), whereas the multivitamin alone was given to the control group (n = 28). Standard antibiotic therapy was given to all patients.RESULTS: Serum zinc concentrations increased in both groups during convalescence; however, zinc supplementation showed a significant effect. The lymphocyte proliferation response in the zinc group increased relative to that in the control group (P = 0.002), but no significant effects were seen on concentrations of cytokines (interleukin 2 and interferon gamma) released from mitogen-stimulated mononuclear cells or on concentrations of cytokines (interleukin 2, interferon gamma, and interleukin 1beta) in feces. Among the antigen [lipopolysaccharide and invasion plasmid-encoded antigen (Ipa)]-specific antibodies, plasma Ipa-specific immunoglobulin G responses at day 30 were significantly higher in the zinc group than in the control group. However, the 2 groups did not differ significantly in the other antigen-specific responses in plasma and stool.CONCLUSION: A 14-d course of zinc supplementation during acute shigellosis increases the lymphocyte proliferation response and the Ipa-specific immunoglobulin G response.

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PMID: 

Photodermatol Photoimmunol Photomed. 2010 Apr ;26(2):66-9. PMID: 20415736

Abstract Title: 

Topical riboflavin attenuates ultraviolet B- and ultraviolet A-induced immunosuppression in humans.

Abstract: 

BACKGROUND: Riboflavin (vitamin B(2)) plays a key role in cellular energy metabolism. We have observed previously that nicotinamide (vitamin B(3)), which is also centrally involved in cellular energy restoration after UV irradiation, is highly immune protective in humans. We thus hypothesized that riboflavin might also confer immune protection.METHODS: We irradiated healthy, nickel-allergic volunteers with narrowband UVA (385 nm) and UVB (300 nm) at separate sites on the lower back. These areas were treated with riboflavin solution or vehicle at 24 h and again at 30 min before UV exposure. Forty-eight hours after irradiation, volunteers were patch tested with nickel-containing Finn chambers, at both irradiated and nonirradiated sites, with and without prior riboflavin treatment. The resulting contact hypersensitivity reactions at each site were then measured 72 h later with a reflectance erythema meter in order to determine and compare the immune suppressive effects of each intervention.RESULTS: We observed that low doses of both UVB and longwave UVA1 were immune suppressive in humans. Topical riboflavin conferred immune protection against both wavebands.CONCLUSIONS: Riboflavin is immune protective in humans, and this may reflect the role of the B group vitamins in cellular energy restoration after UV exposure.

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PMID: 

Br J Nutr. 2013 Aug 28 ;110(3):509-14. Epub 2013 Feb 18. PMID: 23415257

Abstract Title: 

Riboflavin deprivation inhibits macrophage viability and activity – a study on the RAW 264.7 cell line.

Abstract: 

Riboflavin, or vitamin B2, as a precursor of the coenzymes FAD and FMN, has an indirect influence on many metabolic processes and determines the proper functioning of several systems, including the immune system. In the human population, plasma riboflavin concentration varies from 3·1 nM (in a moderate deficiency, e.g. in pregnant women) to 10·4 nM (in healthy adults) and 300 nM (in cases of riboflavin supplementation). The purpose of the present study was to investigate the effects of riboflavin concentration on the activity and viability of macrophages, i.e. on one of theimmunocompetent cell populations. The study was performed on the murine monocyte/macrophage RAW 264.7 cell line cultured in medium with various riboflavin concentrations (3·1, 10·4, 300 and 531 nM). The results show that riboflavin deprivation has negative effects on both the activity and viability of macrophages and reduces their ability to generate an immune response. Signs of riboflavin deficiency developed in RAW 264.7 cells within 4 d of culture in the medium with a low riboflavin concentration (3·1 nM). In particular, the low riboflavin content reduced the proliferation rate and enhanced apoptotic cell death connected with the release of lactate dehydrogenase. The riboflavin deprivation impaired cell adhesion, completely inhibited the respiratory burst and slightly impaired phagocytosis of the zymosan particles. In conclusion, macrophages are sensitive to riboflavin deficiency;thus, a low riboflavin intake in the diet may affect the immune system and may consequently decrease proper host immune defence.

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PMID: 

Libyan J Med. 2013 Oct 7 ;8:22520. Epub 2013 Oct 7. PMID: 24103319

Abstract Title: 

Rose geranium essential oil as a source of new and safe anti-inflammatory drugs.

Abstract: 

BACKGROUND: Since the available anti-inflammatory drugs exert an extensive variety of side effects, the search for new anti-inflammatory agents has been a priority of pharmaceutical industries.AIMS: The aim of the present study was to assess the anti-inflammatory activities of the essential oil of rose geranium (RGEO).METHODS: The chemical composition of the RGEO was investigated by gas chromatography. The major components were citronellol (29.13%), geraniol (12.62%), and citronellyl formate (8.06%). In the carrageenan-induced paw edema, five different groups were established and RGEO was administered orally in three different doses.RESULTS: RGEO (100 mg/kg) was able to significantly reduce the paw edema with a comparable effect to that observed with diclofenac, the positive control. In addition, RGEO showed a potent anti-inflammatory activity by topical treatment in the method of croton oil-induced ear edema. When the dose was 5 or 10µl of RGEO per ear, the inflammation was reduced by 73 and 88%, respectively. This is the first report to demonstrate a significant anti-inflammatory activity of Algerian RGEO. In addition, histological analysis confirmed that RGEO inhibited the inflammatory responses in the skin.CONCLUSION: Our results indicate that RGEO may have significant potential for the development of novel anti-inflammatory drugs with improved safety profile.

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PMID: 

J Invest Dermatol. 2003 May ;120(5):728-37. PMID: 12713573

Abstract Title: 

Glycerol regulates stratum corneum hydration in sebaceous gland deficient (asebia) mice.

Abstract: 

The only known function of human sebaceous glands is the provocation of acne. We assessed here whether sebum influences stratum corneum hydration or permeability barrier function in asebia J1 and 2 J mice, with profound sebaceous gland hypoplasia. Asebia J1 mice showed normal permeability barrier homeostasis and extracellular lamellar membrane structures, but they displayed epidermal hyperplasia, inflammation, and decreased (>50%) stratum corneum hydration, associated with a reduction in sebaceous gland lipids (wax diesters/monoesters, sterol esters). The triglyceride content of both asebia and control stratum corneum was low, consistent with high rates of triglyceride hydrolysis within the normal pilosebaceous apparatus, despite high rates of triglyceride synthesis. Although a mixture of synthetic, sebum-like lipids (sterol/wax esters, triglycerides) did not restore normal stratum corneum hydration to asebia skin, topical glycerol, the putative product of triglyceride hydrolysis in sebaceous glands, normalized stratum corneum hydration, and the glycerol content of asebia stratum corneum was 85% lower than in normal stratum corneum. In contrast, another potent endogenous humectant (urea) did not correct the abnormality. The importance of glycerol generation from triglyceride in sebaceous glands for stratum corneum hydration was demonstrated further by (i) the absence of sebaceous-gland-associated lipase activity in asebia mice, whereas abundant enzyme activity was present in the glands of control mice; and (ii) the inability of high concentrations of topical triglyceride to correct the hydration abnormality, despite the presence of abundant lipase activity in asebia stratum corneum. These results show that sebaceous-gland-derived glycerol is a major contributor to stratum corneum hydration.

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PMID: 

Skin Pharmacol Physiol. 2008 ;21(1):39-45. Epub 2007 Nov 19. PMID: 18025807

Abstract Title: 

Placebo-controlled, double-blind, randomized, prospective study of a glycerol-based emollient on eczematous skin in atopic dermatitis: biophysical and clinical evaluation.

Abstract: 

BACKGROUND/AIMS: Atopic dermatitis (AD) is a frequent, chronic inflammatory disease influenced by local, immunological, genetic and environmental factors. Important symptoms of AD are dry skin, intense pruritus and impaired epidermal barrier function. The therapeutic management of AD is difficult and needs individualized concepts. Moisturizing creams and emollients are useful and important treatment adjuncts for the daily skin care of patients with dry and inflamed skin, e.g. AD. Glycerol is known to increase stratum corneum (SC) hydration, improve epidermal barrier function and decrease clinical signs of inflammation. However, no controlled study on the efficacy of glycerol on barrier function and SC hydration in AD has been published. In the present study, a topical 20% glycerol preparation was compared with its vehicle in patients with AD. The aim of the present study was to evaluate the effect of a single emollient ingredient in AD within the full frame of a phase III drug study.METHODS: 24 patients with AD were treated for 4 weeks twice daily with a glycerol-based emollient in a randomized, double-blind study. Transepidermal water loss, skin capacitance, erythema and skin surface pH were assessed with biophysical, non-invasive instruments. The SCORAD and a local severity score were evaluated. After a wash-out period of 2 weeks, these parameters were assessed in order to quantify the sustained effect of this treatment.RESULTS: SC hydration was significantly improved, and epidermal barrier function was restored under treatment with glycerol-containing cream compared to the glycerol-free placebo. No significant differences were detectable for erythema values, SCORAD and local severity between the glycerol-containing cream and placebo. However, an improvement over time was detectable in the assessed parameters in both groups indicating the importance of emollient treatment in AD.CONCLUSIONS: Glycerol-based emollients have a positive influence on the skin of patients with AD. They enhance the SC hydration. Furthermore, it was possible to evaluate skin care products with a protocol design for efficacy studies of fully registered drugs in a placebo-controlled study.

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PMID: 

Acta Derm Venereol. 2002 ;82(1):45-7. PMID: 12013198

Abstract Title: 

A double-blind study comparing the effect of glycerin and urea on dry, eczematous skin in atopic patients.

Abstract: 

Moisturizing creams have beneficial effects in the treatment of dry, scaly skin, but they may induce adverse skin reactions. In a randomized double-blind study, 197 patients with atopic dermatitis were treated with one of the following: a new moisturizing cream with 20% glycerin, its cream base without glycerin as placebo, or a cream with 4% urea and 4% sodium chloride. The patients were asked to apply the cream at least once daily for 30 days. Adverse skin reactions and changes in skin dryness were assessed by the patient and a dermatologist. Adverse skin reactions such as smarting (a sharp local superficial sensation) were felt significantly less among patients using the 20% glycerin cream compared with the urea-saline cream, because 10% of the patients judged the smarting as severe or moderate when using glycerin cream, whereas 24% did so using urea-saline cream (p

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