Chronic, non-healing wounds represent a major global health challenge, often aggravated by microbial dysbiosis and impaired host responses. Wound healing progresses through four overlapping phases—hemostasis, inflammation, proliferation, and remodeling—yet recent findings reveal that the skin microbiota actively participates in each step through immune, metabolic, and signaling mechanisms. Beneficial microorganisms such as Staphylococcus epidermidis and Lactobacillus plantarum promote tissue repair by inducing antimicrobial peptides and modulating cytokine production, whereas opportunistic pathogens (Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis) delay closure via biofilm formation and proteolytic activity. This review integrates current molecular insights and bibliometric trends to highlight advances and remaining challenges in understanding the wound–microbiome axis. A deeper grasp of these interactions can inform next-generation, microbiome-targeted therapies for chronic wounds.

The leptin–melanocortin pathway is pivotal in appetite and energy homeostasis. Pathogenic variants in genes involved in this pathway lead to severe early-onset monogenic obesity (MO). The MC4R gene plays a central role in leptin–melanocortin signaling, and heterozygous variants in this gene are the most common cause of MO. A targeted gene panel consisting of 52 obesity-related genes was used to screen for variants associated with obesity. Variants were analyzed and filtered to identify potential disease-causing activity and validated using Sanger sequencing. We identified two novel heterozygous variants, c.253A>G p.Ser85Gly and c.802T>C p.Tyr268His, in the MC4R gene in two unrelated patients with morbid obesity and evaluated the functional impact of these variants. The impact of the variants on the MC4R gene was assessed using in silico prediction tools and molecular dynamics simulation. To further study the pathogenicity of the identified variants, GT1-7 cells were transfected with plasmid DNA encoding either wild-type or mutant MC4R variants. The effects of allelic variations in the MC4R gene on cAMP synthesis, MC4R protein level, and activation of PKA, ERB, and CREB signaling pathways in both stimulated and unstimulated ɑ-MSH paradigms were determined for their functional implications. In silico analysis suggested that the variants destabilized the MC4R structure and affected the overall dynamics of the MC4R protein, possibly leading to intracellular receptor retention. In vitro analysis of the functional impact of these variants showed a significant reduction in cell surface receptor expression and impaired extracellular ligand binding activity, leading to reduced cAMP production. Our analysis shows that the variants do not affect total protein expression; however, they are predicted to affect the post-translational localization of the MC4R protein to the cell surface and impair downstream signaling cascades such as PKA, ERK, and CREB signaling pathways. This finding might help our patients to benefit from the novel therapeutic advances for monogenic forms of obesity.

Albumin-coated gold nanoparticles display potential biomedical applications, including cancer research, infection treatment, and wound healing; however, elucidating their interaction with normal cells remains an area with limited exploration. In this study, gold nanorods (GNR) were prepared and coated with bovine serum albumin (BSA) to produce GNR-BSA. The functionalized nanoparticles were characterized based on their optical absorption spectra, morphology, surface charge, and quantity of attached protein. The interaction between GNR-BSA and BSA with normal cells was investigated using human dermal fibroblasts. The cytotoxicity test indicated cell viability between ~63–95% for GNR-BSA over concentrations from 30.0 to 0.47 μg/mL and ~85–98% for BSA over concentrations from 4.0 to 0.0625 mg/mL. The impact of the GNR-BSA and BSA on cell migration potential and wound healing was assessed using scratch assay, and the modulation of cytokine release was explored by quantifying a panel of cytokines using Multiplex technology. The results indicated that GNR-BSA, at 10 μg/mL, delayed the cell migration and wound healing 24 h post-treatment compared to the BSA or the control group with an average wound closure percentage of 6% and 16% at 6 and 24 h post-treatment, respectively. Multiplex analysis revealed that while GNR-BSA reduced the release of the pro-inflammatory marker IL-12 from the activated fibroblasts 24 h post-treatment, they significantly reduced the release of IL-8 (p < 0.001), and CCL2 (p < 0.01), which are crucial for the inflammation response, cell adhesion, proliferation, migration, and angiogenesis. Although GNR-BSA exhibited relatively high cell viability towards human dermal fibroblasts and promising therapeutic applications, toxicity aspects related to cell motility and migration must be considered.

The skin acts as a primary barrier against environmental insults and maintains homeostasis. Injury initiates a wound healing cascade of hemostasis, inflammation, proliferation, and remodeling. In chronic wounds, persistent microbial colonization and inflammation disrupt this process, with bacterial virulence factors acting as key drivers. While the microbiome’s role in chronic wounds is recognized, the effects of individual virulence factors on acute repair remain unclear. Therefore, this study investigated the differential effects of virulence factors derived from five skin-associated bacterial species on acute wound healing dynamics. In this context, virulence factors from Pseudomonas aeruginosa, Staphylococcus aureus, Streptococcus pyogenes, Lactobacillus plantarum, and Enterococcus faecalis were tested on HDF-n cell viability and wound closure, with multiplex ELISA used to assess inflammatory mediator secretion and underlying mechanisms. Overall, virulence factors were generally well tolerated across concentrations (0.05–16 µg/mL) and time points (24, 48 h), with cell viability >80%, except for S. aureus, which reduced viability to ~70% at higher concentrations by 48 h. Wound healing responses varied markedly: S. aureus significantly impaired closure in a dose-dependent manner (~10% closure at 16 µg/µL, 48 h), and E. faecalis similarly delayed repair. In contrast, factors from P. aeruginosa, S. pyogenes, and L. plantarum showed neutral or mildly pro-healing effects. Notably, co-treatment with S. pyogenes partially rescued impairment caused by S. aureus and E. faecalis. Collectively, these findings highlight that bacterial virulence factors have variable impacts on acute wound healing. These findings suggest potential therapeutic applications through targeted modulation or combinations of bacterial factors.

The kinase suppressor of Ras 2 (KSR2) gene is associated with monogenic obesity, and loss-of-function variants in KSR2 have been identified in individuals with severe early-onset obesity. This study investigated KSR2 variants in 9 pediatric patients with severe early-onset obesity in Qatar using whole genome sequencing among a cohort of 240 individuals. We focused on KSR2 variants with a minor allele frequency (MAF) below 1% and a Combined Annotation Dependent Depletion (CADD) score above 13 to identify potential causative variants. Our analysis identified four KSR2 variants: one intronic (c.1765-8G>A) and three missense variants (c.1057G>A, c.1673G>A, and c.923T>C) in nine patients. The intronic variant c.1765-8G>A was the most frequent (seen in six individuals) and had a CADD score of 21.10, suggesting possible pathogenicity. This variant showed a significantly higher allele frequency in the Qatari population compared to the Genome Aggregation Database (gnomAD), indicating a possible founder effect. Molecular modeling of the missense variants revealed structural changes in the protein structure. The study concludes that these four KSR2 variants are associated with monogenic obesity, with an autosomal dominant inheritance pattern. The c.1765-8G>A variant’s prevalence in Qatar underscores its importance in genetic screening for severe obesity. This research advances the understanding of genetic factors in severe early-onset obesity and may inform better management strategies.

The leptin-melanocortin pathway is pivotal in appetite and energy homeostasis. Pathogenic variants in genes involved in this pathway lead to severe early-onset monogenic obesity (MO). The MC4R gene plays a central role in leptin-melanocortin signaling, and variants predominantly heterozygous in this gene are the most common cause of MO. We identified two novel heterozygous variants c,253A>G p.Ser85Gly and c.802T>C p.Tyr268His in the MC4R gene in two unrelated patients with morbid obesity and evaluated the functional impact of these variants. A targeted gene panel consisting of 52 obesity-related genes was undertaken. Variants were analyzed and filtered to identify potential disease-causing and validated using Sanger sequencing. The impact of the variants on the MC4R gene using in silico prediction tools and molecular dynamics simulation was assessed. To further study the pathogenicity of the identified variants, GT1-7 cells were transfected with plasmid DNA encoding either wild-type or mutant MC4R variants. The effects of allelic variations in MC4R gene on cAMP synthesis, MC4R protein level, and activation of ERB and CREB signaling pathways in both stimulated and unstimulated ɑ-MSH paradigms were determined for their functional implications. In-silico analysis suggested that the variants destabilized the MC4R structure and affect the overall dynamics of the MC4R protein, possibly leading to intracellular receptor retention. In-vitro analysis of the functional impact of these variants showed a significant reduction in cell surface receptor expression and impaired extracellular ligand binding activity, leading to reduced cAMP production. In-vitro analysis assays and in silico analysis revealed the pathogenicity of the two novel MC4R variants identified. Our analysis shows that the variants do not affect total protein expression; however, they are predicted to affect the post-translational localization of MC4R protein to the cell surface and impair downstream signaling cascades. This finding might help our patients to benefit from the novel therapeutic advances for monogenic forms of obesity.