Sweat glands are widely distributed in human skin, among which eccrine sweat glands play major roles in heat dissipation and sweat secretion. Sweat secretion is mainly regulated by nervous system and includes two processes of secretion of secretory coil and reabsorption of sweat duct, involving various ion channels and proteins such as calcium ion channel, potassium ion channel, sodium-potassium-chloride co-transporter 1, Best2 protein, aquaporin 5, cystic fibrosis transmembrane conductance regulator, and epithelial sodium ion channel. This paper reviews the nerve conduction system and various ion channels involved in sweat secretion of exocrine sweat glands in order to provide a theoretical basis for the study of regeneration, repair, and transformation of stem cells.
Eccrine Glands/metabolism* ; Humans ; Sweat/metabolism*

BACKGROUND: Sweat secreted by eccrine sweat glands is transported to the skin surface through the lumen. The eccrine sweat gland develops from the initial solid bud to the final gland structure with a lumen, but how the lumen is formed and the mechanism of lumen formation have not yet been fully elucidated. This study aimed to investigate the mechanism of lumen formation of eccrine gland organoids (EGOs). METHODS: Human eccrine sweat glands were isolated from the skin for tissue culture, and the primary cultured cells were collected and cultured in Matrigel for 14 days in vitro. EGOs at different development days were collected for hematoxylin and eosin (H&E) staining to observe morphological changes and for immunofluorescence staining of proliferation marker Ki67, cellular motility marker filamentous actin (F-actin), and autophagy marker LC3B. Western blotting was used to detect the expression of Ki67, F-actin, and LC3B. Moreover, apoptosis was detected using a terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) apoptosis assay kit, and the expression of poly (ADP-ribose) polymerase and Caspase-3 was detected by Western blot. In addition, 3-methyladenine (3MA) was used as an autophagy inhibitor to detect whether the formation of sweat glands can be effectively inhibited. RESULTS: The results showed that a single gland cell proliferated rapidly and formed EGOs on day 4. The earliest lumen formation was observed on day 6. From day 8 to day 14, the rate of lumen formation in EGOs increased significantly. The immunofluorescence and Western blot analyses showed that the expression of Ki67 gradually decreased with the increase in days, while the F-actin expression level did not change. Notably, the expression of autophagy marker LC3B was detected in the interior cells of EGOs as the apoptosis signal of EGOs was negative. Compared with the control group, the autophagy inhibitor 3MA can effectively limit the formation rate of the lumen and reduce the inner diameter of EGOs. CONCLUSION Using our model of eccrine gland 3D-reconstruction in Matrigel, we determined that autophagy rather than apoptosis plays a role in the lumen formation of EGOs.
Apoptosis ; Autophagy ; Eccrine Glands ; Epithelial Cells ; Humans ; Organoids

Hair follicle nevus (HFN) is a rare, benign, follicular hamartoma that most frequently presents as a congenital nodule on the face. We experienced a rare case of HFN on the neck of a 14-year-old boy and performed a pilot immunohistochemical study with cytokeratin 19 (CK19) to compare the staining pattern of hair follicles in HFN and its differential diagnoses, accessory tragus, cervical chondrocutaneous branchial remnants (CCBR) and trichofolliculoma. With hematoxylin and eosin stain, HFN showed numerous tiny hair follicles in the dermis with several sebaceous and eccrine glands, and perifollicular fibrous thickening. With CK19 stain, some hair follicles in HFN and CCBR showed positive expression, a few hair follicles in accessory tragus showed weak expression, and no hair follicles in trichofolliculoma showed expression. The present report supports the view that HFN, accessory tragus and CCBR are within the same spectrum of hamartomas.
Adolescent ; Dermis ; Diagnosis, Differential ; Eccrine Glands ; Eosine Yellowish-(YS) ; Hair Follicle ; Hair ; Hamartoma ; Hematoxylin ; Humans ; Keratin-19 ; Male ; Neck ; Nevus

Eccrine porocarcinoma is a rare malignant tumor arising from the intraepidermal ductal portion of the eccrine sweat gland. It develops either spontaneously or from a long standing benign eccrine poroma. This entity usually affects older people and is commonly located on the lower extremities, the trunk, and the head. We report a case of eccrine porocarcinoma on the left cheek in an 85-year-old male. In our case, the tumor was treated with wide excision and postoperative adjuvant radiation therapy. The patient recovered well without local recurrence and distant metastasis during the 14-month follow-up period. Wide excision and postoperative adjuvant radiation therapy can be considered as a safe and effective treatment option in treating patients with eccrine porocarcinoma.
Aged, 80 and over ; Cheek ; Eccrine Porocarcinoma ; Follow-Up Studies ; Head ; Humans ; Lower Extremity ; Male ; Neoplasm Metastasis ; Poroma ; Radiotherapy, Adjuvant ; Recurrence ; Sweat Gland Neoplasms ; Sweat Glands

Background: Previous studies demonstrate that eccrine sweat glands are innervated by both cholinergic and adrenergic nerves. However, it is still unknown whether the secretory coils and ducts of eccrine sweat glands are equally innervated by the sympathetic nerve fibers. To well understand the mechanisms on sweat secretion and reabsorption, the differential innervation of secretory coils and ducts in human eccrine sweat glands was investigated in the study. Methods: From June 2016 to June 2017, six human skins were fixed, paraffin-embedded, and cut into 5 μm-thick sections, followed by costaining for nerve fiber markers protein gene product 9.5 (PGP 9.5), tyrosine hydroxylase (TH) and vasoactive intestinal peptide (VIP), and eccrine sweat gland markers K7, S100P, and K14 by combining standard immunofluorescence with tyramide signal amplification (IF-TSA). Stained sections were observed under the microscope, photographed, and analyzed. Results: The fluorescent signals of PGP 9.5, TH, and VIP were easily visualized, by IF-TSA, as circular patterns surrounding eccrine sweat glands, but only PGP 9.5 could be observed by standard IF. The IF-TSA method is more sensitivity than standard IF in detecting antigens expressed at low levels. PGP 9.5, TH, and VIP appeared primarily surrounding the secretory coils and sparsely surrounding the sweat ducts. Conclusion Sweat secretion is mainly controlled by autonomic nerves whereas sweat reabsorption is less affected by nerve activity.
Eccrine Glands ; innervation ; Fluorescent Antibody Technique ; Humans ; Nerve Fibers ; Sweat Glands ; innervation ; Vasoactive Intestinal Peptide ; analysis

Eccrine poroma is a benign solitary tumor with acrosyringeal differentiation that usually occurs on the sole or either side of the foot. Rapid growth of eccrine poroma during pregnancy has rarely been reported. We demonstrate a unique case of a 37-year-old pregnant woman who suffered from enlarged eccrine poroma on her left palm, which was tiny for 10 years but suddenly grew to a size of bean-sized reddish brown colored, pedunculated mass during pregnancy. The patient denied a previous history of trauma or infection to the lesion. Histopathologic findings with a shave biopsy were consistent with eccrine poroma. After the tumor was completely removed by the shave biopsy, no recurrence was noted for 5 months.
Adult ; Biopsy ; Eccrine Glands ; Female ; Foot ; Humans ; Poroma* ; Pregnancy* ; Pregnant Women ; Recurrence

Lichen sclerosus et atrophicus (LSA) is a chronic inflammatory dermatosis presenting as white papules and atrophic patches in the anogenital region. Extragenital LSA is rare and commonly affects the neck, thighs, and the trunk. A 68-year-old woman presented with a well-demarcated, whitish linear plaque on the forehead that was observed several months prior to presentation. A biopsy specimen showed hyperkeratosis and thinning of the epidermis and homogenization of collagen in the papillary dermis with a subepidermal cleft. Mild periappendageal lymphocytic infiltration and eccrine gland atrophy secondary to thickening of collagen bundles were observed in the deep dermis. Based on the clinical and histopathological findings, this patient was diagnosed with extragenital LSA and concomitant morphea along the Blaschko's lines.
Aged ; Atrophy ; Biopsy ; Collagen ; Dermis ; Eccrine Glands ; Epidermis ; Female ; Forehead* ; Humans ; Lichen Sclerosus et Atrophicus* ; Lichens* ; Neck ; Scleroderma, Localized ; Skin Diseases ; Thigh

Nevus sebaceous is a common congenital cutaneous hamartoma occurring mainly on the face and scalp. It is well known that secondary neoplasms can be easily observed in the primary lesion. However, a case of trichoblastoma and compound nevus concurrently arising from nevus sebaceous has not been previously reported. A 26-year-old woman presented with a well-demarcated atrophic skin-colored plaque on her scalp from birth. On the plaque, a black dome-shaped round nodule and a brownish nodule with irregular margins were found one week previously without subjective symptoms. Histopathological examination of the central plaque lesion revealed epidermal hyperplasia and hyperplasia of the sebaceous glands and eccrine glands. In addition, ectopic, dilated apocrine glands were revealed in the lower dermis, and the hair follicles remained small and primordial, consistent with nevus sebaceous. A section of the black nodule showed palisading basaloid cells surrounded by abundant fibrous stroma. Nests of nevus cells were found at the dermo-epidermal junction and dermis in the brownish nodule. Based on these findings, the black nodule and brownish nodule were diagnosed as trichoblastoma and compound nevus, respectively. Herein, we report an interesting case of trichoblastoma and compound nevus concurrently arising from nevus sebaceous, which is, to our knowledge, the first such report in the dermatologic literature.
Adult ; Apocrine Glands ; Dermis ; Eccrine Glands ; Female ; Hair Follicle ; Hamartoma ; Humans ; Hyperplasia ; Nevus* ; Parturition ; Scalp ; Sebaceous Glands

Primary cutaneous mucinous carcinoma (PCMC) is a rare low-grade malignant neoplasm derived from the eccrine glands. PCMC most commonly arises in the head and neck, with the eyelid being the most common site of origin. This case report describes a 51-year-old male with a painless, pigmented superficial nodular lesion over his right lower eyelid. The lesion was considered to be benign, and the initial treatment was simple excision with a 3-mm margin. However, histologic examination revealed the diagnosis of PCMC, and the patient underwent re-excision of the tumor site with an additional 3-mm margin from the initial scar. Histologic study of this second margin was free of any malignant cells. The patient experienced no postoperative complication or recurrence after 2 years. In our case, the skin lesion had benign morphologic findings and was strongly suspected to be a benign mass. Physicians should be aware of this tumor and be able to differentiate it from benign cystic or solid eyelid lesions.
Adenocarcinoma, Mucinous* ; Cicatrix ; Diagnosis ; Eccrine Glands ; Eyelids* ; Head ; Humans ; Male ; Middle Aged ; Mucins* ; Neck ; Postoperative Complications ; Recurrence ; Skin ; Skin Neoplasms

Primary cutaneous mucinous carcinoma (PCMC) is a rare low-grade malignant neoplasm derived from the eccrine glands. PCMC most commonly arises in the head and neck, with the eyelid being the most common site of origin. This case report describes a 51-year-old male with a painless, pigmented superficial nodular lesion over his right lower eyelid. The lesion was considered to be benign, and the initial treatment was simple excision with a 3-mm margin. However, histologic examination revealed the diagnosis of PCMC, and the patient underwent re-excision of the tumor site with an additional 3-mm margin from the initial scar. Histologic study of this second margin was free of any malignant cells. The patient experienced no postoperative complication or recurrence after 2 years. In our case, the skin lesion had benign morphologic findings and was strongly suspected to be a benign mass. Physicians should be aware of this tumor and be able to differentiate it from benign cystic or solid eyelid lesions.
Adenocarcinoma, Mucinous* ; Cicatrix ; Diagnosis ; Eccrine Glands ; Eyelids* ; Head ; Humans ; Male ; Middle Aged ; Mucins* ; Neck ; Postoperative Complications ; Recurrence ; Skin ; Skin Neoplasms