Altered Th17/Treg balance and therapeutic targeting of RORγ in primary focal hyperhidrosis

Abstract

Background: Primary focal hyperhidrosis (PFH) significantly impacts patients' physical and mental health, yet its underlying mechanisms remain unclear.

Methods: This study involved 80 healthy controls and 60 patients each with primary palmar (PPH), craniofacial (PCH), or axillary hyperhidrosis (PAH). Peripheral blood mononuclear cells (PBMCs) were analyzed via flow cytometry to assess Th17 and Treg cell populations. Cytokine levels were measured in patient serum using ELISA, while sweat gland tissue from PAH patients underwent gene expression analysis. A pilocarpine-induced mouse model of hyperhidrosis was used to test SR2211, a RORγ inverse agonist.

Results: PFH patients exhibited a disrupted Th17/Treg balance, with increased Th17 and decreased Treg cells across all subtypes compared to controls. Elevated IL-17 and IL-6 and reduced IL-10 and TGF-β1 levels were observed in PFH serum. Sweat glands showed increased RORγt and decreased FOXP3 expression. In mice, SR2211 treatment reduced sweat secretion, secretory granules, and serum acetylcholine. It also lowered Th17 infiltration, serum IL-17/IL-6, and IL-17A expression in sweat glands.

Discussion: PFH is associated with a Th17/Treg immune imbalance. SR2211 alleviated hyperhidrosis and Th17-related inflammation in mice, highlighting the potential of targeting the RORγ-Th17 axis as a therapeutic strategy for PFH.

Keywords: RORγ; Th17 cell; Treg cell; immune imbalance; primary focal hyperhidrosis (PFH).

Figure 1

Comparisons of Th17 (A), Treg (B) lymphocyte subpopulations and Th17/Treg ratio (C) in peripheral blood from patients with primary focal hyperhidrosis (PFH, n = 180) and healthy controls (HC, n = 80). Data were shown as mean ± SD. ***p < 0.001. Unpaired t test with Welch’s correction. ROC analysis of Th17 (D), Treg (E) lymphocyte subpopulations and Th17/Treg ratio (F) in peripheral blood to identify primary focal hyperhidrosis patients from healthy controls. Comparisons of Th17 (G), Treg (H) lymphocyte subpopulations and Th17/Treg ratio (I) in peripheral blood from healthy controls (n = 80), primary palmar hyperhidrosis patients (n = 60), primary axillary hyperhidrosis patients (n = 60) and primary cranimofacial hyperhidrosis patients (n = 60). The data were presented with mean ± SD. ***p < 0.001 from Brown-Forsythe ANOVA test followed by Dunnett’s T3 multiple comparisons test.

Figure 2

Comparisons of serum IL-17 (A), IL-6 (B), IL-10 (C) and TGF-β1 (D) among healthy controls (n = 80), primary palmar hyperhidrosis patients (n = 60), primary axillary hyperhidrosis patients (n = 60) and primary cranimofacial hyperhidrosis patients (n = 60). The data were presented with mean ± SD. **p < 0.01, ***p < 0.001 from Brown-Forsythe ANOVA test followed by Dunnett’s T3 multiple comparisons test.

Figure 3

Expression changes of RORγt and FOXP3 in sweat gland tissues of primary focal hyperhidrosis patients. The mRNA levels of RORγt (A) and FOXP3 (B) in sweat gland tissues from healthy controls, primary palmar hyperhidrosis patients, primary axillary hyperhidrosis patients and primary cranimofacial hyperhidrosis patients were measured by qRT-PCR. n = 6 for each group. The protein levels of RORγt and FOXP3 in sweat gland tissues homogenate from healthy controls, primary palmar hyperhidrosis patients, primary axillary hyperhidrosis patients and primary cranimofacial hyperhidrosis patients were measured by Western blotting (C). β-actin was used as a loading control and the expressions were normalized to HC (D, E). n = 6 for each group. The data were presented with mean ± SD. ***p < 0.001 from Brown-Forsythe ANOVA test followed by Dunnett’s T3 multiple comparisons test.

Figure 4

SR2211, the inverse agonist of RORγ, attenuated the sweat secretion and Th17 lymphocyte related inflammatory response in hyperhidrosis mice. Mice were administered with vehicle or SR2211 for one week before the induction of hyperhidrosis, as shown in (A). The number of black dots were calculated (B). The number of sweat secretory granules were counted (C) and the concentration of acetylcholine in serum was detected by ELISA (D). Th17 lymphocyte subpopulations in peripheral blood of the mice were compared (E). The serum levels of IL-17 (F) and IL-6 (G) were measured by ELISA. Western blotting was used to detect the protein expression of IL-17A in the sweat gland of hyperhidrosis mice (H). GAPDH was used as a loading control and the expressions were normalized to control (I). The data were presented with mean ± SD. n = 8 for each group. **p < 0.01, ***p < 0.001 from Brown-Forsythe ANOVA test followed by Dunnett’s T3 multiple comparisons test.