The hair cycle is composed of four primary phases: anagen, catagen, telogen, and exogen. Anagen is a highly mitotic phase characterized by the production of a hair shaft from the hair follicle, whereas catagen and telogen describe regression and the resting phase of the follicle, respectively, ultimately resulting in hair shedding. While 9% of hair follicles reside in telogen at any time, a variety of factors promote anagen to telogen transition, including inflammation, hormones, stress, nutritional deficiency, poor sleep quality, and cellular division inhibiting medication. Conversely, increased blood flow, direct stimulation of the hair follicle, and growth factors promote telogen to anagen transition and subsequent hair growth. This review seeks to comprehensively describe the hair cycle, anagen and telogen balance, factors that promote anagen to telogen transition and vice versa, and the clinical utility of a variety of lab testing and evaluations. Ultimately, a variety of factors impact the hair cycle, necessitating a holistic approach to hair loss.

Mitochondria are eukaryotic cellular organelles that function in energy metabolism, ROS production, and programmed cell death. Cutaneous epithelial and hair follicle dermal papilla cells are energy-rich cells that thereby may be affected by mitochondrial dysfunction and DNA mutation accumulation. In this review, we aimed to summarize the medical literature assessing dermatologic conditions and outcomes associated with mitochondrial dysfunction. A search of PubMed and Embase was performed with subsequent handsearching to retrieve additional relevant articles. Mitochondrial DNA (mtDNA) deletions, mutation accumulation, and damage are associated with phenotypic signs of cutaneous aging, hair loss, and impaired wound healing. In addition, several dermatologic conditions are associated with aberrant mitochondrial activity, such as systemic lupus erythematosus, psoriasis, vitiligo, and atopic dermatitis. Mouse model studies have better established causality between mitochondrial damage and dermatologic outcomes, with some depicting reversibility upon restoration of mitochondrial function. Mitochondrial function mediates a variety of dermatologic conditions, and mitochondrial components may be a promising target for therapeutic strategies.

Bacteriophages, also known as phages, are viruses that selectively target and infect bacteria. In addition to bacterial dysbiosis, dermatologic conditions such as acne, psoriasis, and atopic dermatitis are characterized by a relative reduction in the abundance of phages and the overgrowth of the corresponding bacteria. Phages often exhibit high specificity for their targeted bacteria, making phage-replacement therapy a promising therapeutic strategy for the control of pathogenic bacteria in dermatologic disease. Novel therapeutic strategies regulating pathogenic bacteria are especially necessary in light of growing antibiotic resistance. In this review, we aimed to review the medical literature assessing phage dysbiosis and therapeutic trials in dermatology. Ultimately, studies have depicted promising results for the treatment of acne, psoriasis, and atopic dermatitis but are limited by low sample sizes and the omission of control groups in some trials. Additional work is necessary to validate the efficacy depicted in proof-of-concept trials and to further determine optimal treatment vehicles, administration mechanisms, and dosing schedules. This review provides the necessary framework for the assessment of phage efficacy in future trials.

(1) Background: The pomegranate fruit (Punica granatum L.) has been widely used in traditional medicine and has increasingly gained popularity among consumers in order to manage different facets of health. The objective of this study was to evaluate the effects of the fruit extract of P. granatum L. on different parameters of skin health. (2) Methods: A prospective, double-blind placebo-controlled study was conducted on both healthy males and females aged 25–55 years. Subjects were supplemented with a standardized punicalagin enriched oral pomegranate extract [Pomella^® (Verdure Science, Noblesville, IN, USA), PE group] or a placebo (control group) daily for four weeks. Changes in wrinkle severity, facial biophysical properties, skin microbiome, and the gut microbiome were assessed. (3) Results: The PE group had significant reductions in wrinkle severity (p < 0.01) and a decreasing trend in the forehead sebum excretion rate (p = 0.14). The participants in the PE group with a higher relative abundance of Eggerthellaceae in the gut had a decrease in their facial TEWL (p < 0.05) and wrinkle severity (p = 0.058). PE supplementation led to an increase in the Staphylococcus epidermidis species and the Bacillus genus on the skin. (4) Conclusions: Overall, the study demonstrated improvements in several biophysical properties, wrinkles, and shifts in the skin microbiome with oral PE supplementation in healthy subjects.

Soybean, a legume native to Southeast Asia, serves many nutritional and medical purposes due to its rich source of phytochemicals and its antioxidant activity. Many animal and in vitro studies have demonstrated its potential impact on dermatologic health. The objective of this review is to investigate the clinical response of soy-based oral supplementation or topical application on dermatologic outcomes. A systematic review of studies assessing soy supplementation or application was performed in January 2023. Databases included PubMed, Embase, Cochrane, and Natural Medicines, and studies assessing any formulation that included soybean or associated products were included. Thirty studies met the inclusion criteria and are included in the review; 13 of these studies assessed oral supplementation and 17 assessed topical application. Topical and oral supplementation demonstrated efficacious results for a variety of dermatologic parameters, including chronological or photoaging parameters, skin barrier status, hydration, hyperpigmentation, dermal network composition, erythema, hair and nail parameters, acne lesion counts, and vulvar lichen sclerosis scores. Factors associated with aging, such as wrinkle area and depth, were most frequently assessed among the studies, and both topical and oral studies demonstrated efficacy. Effects are likely mediated by dermal compositional changes, such as increased collagen and/or elastic fiber numbers. Transepidermal water loss measurements, an indicator of skin barrier status, were frequently obtained among the studies, although improvement was more likely achieved with topical application compared to oral supplementation. The results of this review highlight the utility of soy-based products for a variety of dermatologic applications, although future studies are required to determine optimal formulations and application routes for intended outcomes.

Background: Small intestinal bacterial overgrowth (SIBO) is a common, yet underdiagnosed, gut condition caused by gut dysbiosis. A previous study has shown the potential of herbal therapy, providing equivalent results to rifaximin. Objectives: The objective of this study was to assess how the use of an oral botanical regimen may modulate the gut microbiome, facial erythema, and intestinal permeability in those with SIBO. Methods: This was an open-label prospective study of adults that had lactulose breath test-confirmed SIBO. Participants received a 10-week oral supplementation of a Biocidin liquid tincture and GI Detox+. If participants were found to be non-responsive to treatment after 10 weeks with a persistently positive lactulose breath test, a third oral supplement, Olivirex, was administered for an additional 4 weeks. Lactulose breath tests were administered at baseline, weeks 6, 10, and 14 to assess for SIBO status. A high-resolution photographic analysis system was utilized to analyze changes in facial erythema. Stool sample collections and venipuncture were performed to analyze the gut microbiome and intestinal permeability. Results: A total of 33 subjects were screened with breath testing, and 19 subjects were found to have SIBO. Three of the subjects withdrew during the screening period prior to baseline, and sixteen subjects enrolled. Four subjects dropped out after baseline. Hydrogen-dominant SIBO was the most common subtype of SIBO, followed by methane and hydrogen sulfide. The botanical regimen was most effective for hydrogen- and hydrogen sulfide-dominant SIBO, leading to negative breath test results at week 10 in 42.8% and 66.7% of participants, respectively. Compared to baseline, supplementation with the botanical regimen led to positive shifts in short-chain fatty acid-producing bacteria such as A. muciniphila, F. prausnitzii, C. eutectus, and R. faecis by 31.4%, 35.4%, 24.8%, and 48.7% percent at week 10, respectively. The mean abundance of Firmicutes decreased by 20.2%, Bacteroides increased by 30%, and the F/B ratio decreased by 25.4% at week 10 compared to baseline. At week 10, there was a trending 116% increase in plasma LPS/IgG (p = 0.08). There were no significant changes in plasma zonulin, DAO, histamine, DAO/histamine, LPS/IgG, LPS/IgA, or LPS/IgM. Facial erythema was not statistically different at week 6, but at week 10, there was a 20% decrease (p = 0.001) in redness intensity. Among the patients that extended to week 14, there was no statistical change in erythema. Conclusions: Supplementation with an antimicrobial botanical supplemental regimen may have therapeutic potential in hydrogen and hydrogen-sulfide subtypes of SIBO. Furthermore, the botanical supplemental regimen may reduce facial erythema, increase SCFA-producing bacteria, decrease the F/B ratio, and modulate markers of intestinal permeability.