Ficoll density gradient sedimentation isolation of pelage hair follicle mesenchymal stem cells from adult mouse back skin: a novel method for hair follicle mesenchymal stem cells isolation

Background

Hair follicle mesenchymal stem cells (HF-MSCs) have great potential for cell therapy. Traditional method to isolate whisker HF-MSC is time-consuming and few in cell numbers. How to quickly and conveniently obtain a large number of HF-MSC for experimental research is a problem worth exploring.

Methods

Two-step Ficoll Density Gradient Sedimentation (FDGS) was performed to isolate pelage HF-MSC from adult mice. The characteristic of the isolated cells was identified and compared with whisker HF-MSC by immunofluorescence staining, flow cytometry, three-lineage differentiation and hair follicle reconstruction. Pelage HF-MSC and exosomes were injected into the dorsal skin of mice as well as hair follicle organ culture to explore its role in promoting hair growth. The cells and exosomes distribution were located by immunofluorescence staining.

Results

Isolated pelage HF-MSC expressed similar markers (ALP, Versican, NCAM, Nestin), showed similar growth pattern, possessed similar mesenchymal stem cells function and hair follicle induction ability as whisker HF-MSC. A large number of cells can be obtained with fewer mice compared to traditional method. Injected pelage HF-MSC promoted hair growth by secreting exosomes.

Conclusion

A large number of Pelage HF-MSC can be isolated by FDGS, which can promote hair growth by secreting exosomes which may target the dermal papilla and hair matrix region of host hair follicle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-03051-3.

Frontal-Temporal Triangle Area Hair for Eyebrow Restoration in Asians: A Comparative Study With Periauricular and Occipital Hair

BACKGROUND

The frontal-temporal triangle area (FTTA) hair has a slow growth rate and thin caliber, which are similar to those of eyebrow hair. However, a comparison of cosmetic outcomes between FTTA and other scalp hair grafts in eyebrow transplantation has not been performed.

OBJECTIVE

To compare the cosmetic outcomes of FTTA hair and periauricular and occipital area (POA) hair in eyebrow restoration.

METHODS

A retrospective analysis of 155 patients with FTTA or POA hair transplants was performed. Comparative variables included patient characteristics, hair density, diameter, percentage of one-hair follicular units (FUs), number of transplanted FUs, harvesting time, transection rate, hair survival rate, frequency of eyebrow trimming, and patient satisfaction.

RESULTS

There was a significant difference in hair density, diameter, percentage of one-hair FUs, and harvesting time between the FTTA and POA hair transplants. The FTTA hair grew significantly slower than the POA hair did. The patients in the FTTA group trimmed their postoperative eyebrows at a significantly longer interval than those in the POA group. The percentage of patients who were very satisfied with the surgery results was higher in the FTTA group.

CONCLUSION

The FTTA hair grafts can provide aesthetically pleasing cosmetic results in eyebrow restoration.

Abstract 5600: Glycopeptides promote anti-cancer immune response against solid tumors

Only a fraction of patients benefits from immune checkpoint inhibitors (ICI). Tumor cells exhibit a distinct glycosylation pattern and supplementation of glycans has the potential to promote response and overcome resistance to ICI, thus addressing an urgent clinical need. Using a subcutaneous tumor mouse model, we investigated whether two glycopeptide-based test items reduce tumor burden when orally administered alone or in combination with ICI.

C57/BL6 mice were supplemented with 3% GNU-201 (n=10) or 3% GNU-101 (n=10) in the drinking water starting 14 days prior to tumor cell injection (d-14), while control mice (n=10) received normal drinking water. On day 0, all mice were injected subcutaneously with YUMM1.7 melanoma cells in each flank. On days 6, 9 and 12, mice in each group received anti-PD1 antibody or an isotype control. Tumor size was measured every 3rd day. On day 15, the mice were sacrificed to analyze tumor weight and tumor infiltrating immune cells. 16S rDNA sequencing of fecal samples was performed on days -14, 0 and 14.

GNU-201 and GNU-101 supplementation was well tolerated, no difference in water consumption and no abnormal behavior were detected that would indicate adverse effects of the products. While anti-PD1 on its own had no effect on tumor growth, we observed reduced tumor growth in the GNU-201+anti-PD1, GNU-101 and GNU-101+anti-PD1-treated groups, resulting in a significantly reduced tumor volume in these three groups on day 15.

Administration of the two test items had a clear effect on anti-tumor T cell responses. In combination with anti-PD1, GNU-201 promoted the overall abundance of T cells, and among those the proportion of CD8+ T cells and IFNγ producing CD4+ T cells. Even in absence of anti-PD1, GNU-201 promoted the number of IFNγ+ CD8+ T cells, indicating that GNU-201 did not only promote tumor infiltration but also activation of CD8+ T cells, which are known to directly kill tumor cells. Finally, GNU-201+anti-PD1 resulted in significantly increased levels of Perforin and TNFα producing CD8+ T cells. With GNU-101 there was a trend towards elevated numbers of T cells and TNFα+ CD4 T cells. In mice that received GNU-101 with anti-PD1, we observed significantly elevated levels of TNFα+ CD8+ T cells and a trend towards higher numbers of IFNγ+ CD8+ T cells.

GNU-201 and GNU-101 induced a significant modulation of the gut microbiota. In particular, the products promoted the growth of Akkermansia spp., a genus previously associated with anti-tumor immunity.

In conclusion, GNU-201 and GNU-101 are both able to boost an anti-tumor immune response upon PD1 inhibition and GNU-101 shows moderate anti-tumor effects on its own. The response is linked with tumor-infiltration and activation of T cells and seems to be associated with changes in the gut microbiome. This study highlights a potential therapeutic role for glycopeptides in boosting anti-tumor immunity in response to ICI therapy.

Citation Format: Marianne R. Spalinger, Romain Wyss, Sara Vidal, Yong Miao, Michael Scharl, Yemi Adesokan. Glycopeptides promote anti-cancer immune response against solid tumors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5600.

Exploiting GLAAD molecules to drive an antitumor immune response in a colorectal cancer mouse model

2565

Background: Only a minority of colorectal cancer (CRC) patients benefit from immune checkpoint inhibitors (ICI), with less than half of eligible patients responding to the treatment. Abnormal glycosylation of tumor cells is a signature of cancer development. Here, we described novel immunomodulatory molecules, named GLAAD (glycopeptides with adjuvant and tumor-associated antigen delivery). We hypothesized that GLAAD, by sharing similarities with aberrant glycans expressed in many cancers, may be a safe and effective treatment strategy to promote response and overcome resistance to ICI, thus addressing an urgent clinical need. Using a CRC mouse model, we tested whether two GLAAD candidates reduce tumor burden when orally administered alone or in combination with ICI. Methods: C57/BL6J mice were supplemented with 3% GNU-201 or 3% GNU-101 in the drinking water starting 14 days prior to tumor cell injection (d-14), while control mice received normal drinking water. On day 0, all mice were injected subcutaneously with MC38 CRC cells in each flank. On days 6, 9, 12, and 15, mice in each group received anti-PD1 antibody (aPD1) or an isotype control. Tumor size was measured every 3rd day. On day 18, the mice were sacrificed. Results: The aPD1 therapy alone showed a limited anti-tumor efficacy overall. Groups treated with GNU-201, GNU-101, GNU-201+aPD1 or GNU-101+aPD1 exhibited reduced growth, resulting in a significantly reduced tumor volume vs control on day 18. In contrast, GLAAD candidates alone significantly reduced tumor volume compared with control and led to a numerically larger decrease than aPD1 treatment alone, suggesting a higher efficacy. When analyzing tumor infiltrating myeloid cells on day 18, no differences were seen for neutrophils or dendritic cells but the proportion of macrophages was decreased in mice receiving GNU-201 or GNU-101. GNU-101 resulted in reduced serum levels of IL-10, a molecule participating in the suppression of antitumor immune responses. The tested GLAAD candidates stimulated robust anti-tumor T cell responses. GNU-201 and GNU-101 supplementation alone or in combination with aPD1 increased the proportion of T cells and among those CD8+ T cells, IFNγ producing CD4+ T cells, IFNγ+ and perforin+ CD8+ T cells. GNU-101 and GNU-201 elicited memory T cell responses after priming of the mice, measured as the ex vivo recall response (CD69 expression) of CD8+ T cells isolated from the tumor. Conclusions: GNU-201 and GNU-101 as standalone treatment induce a strong anti-tumor response that is as good as or even better than aPD1 alone. The therapeutic efficacy is associated with increased tumor infiltration and activation of T cells, in particular CD8+ T cells, highlighting the role of these GLAAD candidates as potent adjuvants in supporting specific tumor-associated antigen recognition by the immune system.

[Comparison of distal pancreatectomy with celiac axis resection and sub-adventitial divestment technique for locally advanced or borderline resectable pancreatic body cancer]

Objective: To compare the outcomes of modified Appleby procedure and sub-adventitial divestment technique for locally advanced or borderline resectable pancreatic body cancer. Methods: A total of consecutive 58 patients(33 males and 25 females) who were diagnosed as locally advanced or borderline resectable pancreatic body cancer and underwent distal pancreatectomy at Pancreas Center, First Affiliated Hospital of Nanjing Medical University between September 2013 and May 2019 were retrospectively reviewed. The age(M(IQR)) was 62(9)years(range: 43 to 79 years). Thirty-one patients underwent distal pancreatectomy with celiac axis resection (DP-CAR) and 27 patients underwent distal pancreatectomy with sub-adventitial divestment technique(SDT). Perioperative parameters and follow-up data of these patients were analyzed. Quantitative data were compared with Wilcoxon test while categorical variables were compared with χ2 test or Fisher's exact test. Survival results were estimated by the Kaplan-Meier survival method with a Log-rank test. Results: There were no differences in age,gender,body mass index,abdominal symptoms,comorbidity or preoperative serum CA19-9 between two groups(all P>0.05). Obvious preoperative weight loss was more common in the group of SDT(48.1%(13/27) vs. 19.4%(6/31),χ²=5.431,P=0.020). Longer operative time(310(123) minutes vs. 254(137)minutes, Z=2.277,P=0.023),higher rate of combined organ resection(41.9%(13/31) vs. 14.8%(4/27),χ²=5.123,P=0.041) and longer postoperative hospital stay(15(10) days vs. 11(5)days,Z=2.292,P=0.022) were observed in the group of DP-CAR. Moreover,rate of overall morbidities was also higher (71.0%(22/31) vs. 29.6%(8/27),χ2=9.876,P=0.003),implicated by clinically relevant postoperative pancreatic fistula(61.3%(19/31) vs. 29.6%(8/27),χ2=5.814,P=0.020) in the DP-CAR group. Tumor size of the DP-CAR group was bigger(4.9(1.5)cm vs. 4.0(1.2)cm,Z=2.343,P=0.019) but no difference was seen between the DP-CAR group and SDT group in R0+R1(<1 mm) resection rate (84.0%(21/25) vs. 90.0%(18/20),P=0.678) and LNR(12.0(23.0)% vs. 9.0(18.0)%,Z=1.238,P=0.216),as well as median disease free survival(11.7 months vs. 11.4 months,Z=0.019,P=0.892) and median overall survival(16.3 months vs. 13.7 months,Z=0.172,P=0.679). Conclusions: Both DP-CAR and distal pancreatectomy with SDT are relatively safe and feasible for locally advanced or borderline resectable pancreatic body cancer. Compared with arterial resection,SDT may contribute to lower rates of postoperative complications and shorter duration of hospitalization,but no significant benefit is seen in long-term survival.

Relieving postoperative pain using tumescent solution with ropivacaine in follicular unit excision

BACKGROUND

Local tumescent anesthesia relieves postoperative pain.

OBJECTIVE

To compare the effect of injecting a tumescent solution with/without ropivacaine on postoperative pain.

METHODS

A randomized, double-blind control study was conducted in 314 patients who underwent first follicular unit excision after obtaining informed consent and ethics committee approval. The patients were randomly divided into three groups: intra-groups (group 1, injected with tumescent solution with ropivacaine; group 2, without ropivacaine) and inter-group (group 3, right-head/left-head side with/without ropivacaine). Postoperative pain was recorded using the 5-point Wong-Baker Faces Pain Scale. No preoperative analgesic was administered to any patient. The survival rate of hair follicles was measured using dermoscopy during follow-up. Data were statistically analyzed.

RESULTS

Of the 314 patients included in the study, 166 were men and 148 were women with a mean age of 32.15±4.58 (range, 25-45) years. Postoperative pain with ropivacaine was significantly more relieved compared to that without ropivacaine in both groups (P<0.05). There was no significant difference between sex and survival rate of hair follicles in the intra- or inter-group.

CONCLUSION

A tumescent solution with ropivacaine has proven to relieve postoperative pain and is a safe and valuable form of local anesthesia in follicular unit excision.

3D bioprinting of a gelatin-alginate hydrogel for tissue-engineered hair follicle regeneration

Hair follicle (HF) regeneration remains challenging, principally due to the absence of a platform that can successfully generate the microenvironmental cues of hair neogenesis. Here, we demonstrate a 3D bioprinting technique based on a gelatin/alginate hydrogel (GAH) to construct a multilayer composite scaffold simulating the HF microenvironment in vivo. Fibroblasts (FBs), human umbilical vein endothelial cells (HUVECs), dermal papilla cells (DPCs), and epidermal cells (EPCs) were encapsulated in GAH (prepared from a mixture of gelatin and alginate) and respectively 3D-bioprinted into the different layers of a composite scaffold. The bioprinted scaffold with epidermis- and dermis-like structure was subsequently transplanted into full-thickness wounds in nude mice. The multilayer scaffold demonstrated suitable cytocompatibility and increased the proliferation ability of DPCs (1.2-fold; P < 0.05). It also facilitated the formation of self-aggregating DPC spheroids and restored DPC genes associated with hair induction (ALP, β-catenin, and α-SMA). The dermal and epidermal cells self-assembled successfully into immature HFs in vitro. HFs were regenerated in the appropriate orientation in vivo, which can mainly be attributed to the hierarchical grid structure of the scaffold and the dot bioprinting of DPCs. Our 3D printed scaffolds provide a suitable microenvironment for DPCs to regenerate entire HFs and could make a significant contribution in the medical management of hair loss. This method may also have broader applications in skin tissue (and appendage) engineering. STATEMENT OF SIGNIFICANCE: Hair loss remains a challenging clinical problem that influences quality of life. Three-dimensional (3D) bioprinting has become a useful tool for the fabrication of tissue constructs for transplantation and other biomedical applications. In this study, we used a 3D bioprinting technique based on a gelatin/alginate hydrogel to construct a multi-layer composite scaffold with cuticular and corium layers to simulate the microenvironment of dermal papilla cells (DPCs) in the human body. This new approach permits the controllable formation of self-aggregating spheroids of DPCs in a physiologically relevant extracellular matrix and the initiation of epidermal-mesenchymal interactions, which results in HF formation in vivo. The ability to regenerate entire HFs should have a significant impact on the medical management of hair loss.

Efficacy assessment for low-level laser therapy in the treatment of androgenetic alopecia: a real-world study on 1383 patients

Low-level laser therapy (LLLT) has been a treatment modality by many androgenetic alopecia (AGA) patients in recent years. It remained unclear as to how long the treatment regime should be maintained, and which characteristics of patients should this be recommended. A real-world study was carried out with an FDA-cleared low-level laser helmet for 1383 patients. Ordinal logistic regression analysis with propensity score matching (PSM) was used to investigate the factors related to efficacy assessment. More than 80% of users were between 18 and 40 years old. The median use times were 133 for mild AGA patients and 142 for moderate-to-severe AGA patients, which equated to 38 weeks and 40 weeks, respectively. The overall clinical effectiveness was nearly 80%. PSM analysis revealed that gender (P = 0.002), use period (P = 0.068), scalp conditions with dandruff, rash, and itchy symptoms were associated with the grading of efficacy assessment. Male users (ordinal OR: 1.35, CI: (1.01, 1.79)); use for more than 180 times or use period for 1 year (ordinal OR: 1.40, CI: (1.11, 1.96)); and those with scalp dandruff (ordinal OR: 1.34, CI: (1.01, 1.87)), rash (ordinal OR: 1.47, CI: (1.04, 2.07)), and itchy symptoms (ordinal OR: 1.51, CI: (1.12, 2.03)) had better efficacy assessments. The recommended treatment regime with low-level laser helmet was more than 1 year or 180 use times. Male patients with dandruff, rash, and itchy symptoms in scalps tended to have a better efficacy assessment.

[Comparative clinical efficacy analysis of pancreatoduodenectomy for distal bile duct and pancreatic head cancer: a report of 1 005 cases]

Objective: To compare and analyze the clinical efficacy of pancreaticoduodenectomy for distal bile duct cancer and pancreatic head cancer. Methods: Clinical data of 1 005 patients who underwent pancreaticoduodenectomy and postoperative pathological examination confirmed the diagnosis of distal bile duct cancer and pancreatic head cancer at the Pancreas Center of the First Affiliated Hospital of Nanjing Medical University from January 2016 to December 2020 were analyzed retrospectively. There were 112 cases in the distal bile duct cancer group, 71 males and 41 females,with age (M(IQR)) of 65(15) years(range: 40 to 87 years); 893 cases in the pancreatic head cancer group, 534 males and 359 females,with age of 64(13)years(range: 16 to 91 years). The differences between clinicopathological characteristics and postoperative overall survival of the two groups were analyzed by χ² test, Fisher's exact probability method, rank sum test or log-rank test, respectively. The difference in postoperative overall survival between the two groups was compared using Kaplan-Meier method after propensity score matching (1∶1). Results: Compared with the pancreatic head cancer group,the distal bile duct cancer group had shorter operative time (240.0(134.0) minutes vs. 261.0(97.0) minutes, Z=2.712, P=0.007),less proportion of combined venous resection (4.5% (5/112) vs. 19.4% (173/893), χ²=15.177,P<0.01),smaller tumor diameter (2.0(1.0) cm vs. 3.0(1.5) cm,Z=10.567,P<0.01),higher well/moderate differentiation ratio (51.4% (56/112) vs. 38.0% (337/893), χ²=7.328, P=0.007),fewer positive lymph nodes (0(1) vs. 1(3), Z=5.824, P<0.01),and higher R0 resection rate (77.7% (87/112) vs. 38.3%(342/893), χ²=64.399, P<0.01),but with a higher incidence of overall postoperative complications (50.0% (56/112) vs. 36.3% (324/892), χ²=7.913,P=0.005),postoperative pancreatic fistula (28.6% (32/112) vs. 13.9% (124/893), χ²=16.318,P<0.01),and postoperative abdominal infection (21.4% (24/112) vs. 8.6% (77/892), χ²=18.001,P<0.01). After propensity score matching, there was no statistical difference in postoperative overall survival time between patients in the distal bile duct cancer group and the pancreatic head cancer group (50.6 months vs. 35.1 months,Z=1.640,P=0.201),and multifactorial analysis showed that tumor site was not an independent risk factor affecting the prognosis of patients in both groups after matching (HR=0.73,95%CI:0.43 to 1.23,P=0.238). Conclusions: Patients with distal bile duct cancer are more likely to benefit from early diagnosis and surgical treatment than patients with pancreatic head cancer,but with a relative higher postoperative complication rates. The different tumor origin site is not an independent risk factor for prognosis of patients with distal bile duct cancer and pancreatic head cancer after propensity score matching.

Keratoacanthoma or cutaneous squamous cell carcinoma revealing a DNA mismatch repair default (Muir-Torre Syndrome)

Keratoacanthoma (KA) and well-differentiated cutaneous squamous cell carcinoma (cSCC) are hardly distinguishable clinically and histologically. They both can be seen in patients with hereditary non-polyposis colorectal cancer (HNPCC) or Lynch Syndrome, corresponding to DNA microsatellite instability. In our case, a young man had the excision of two rapidly growing skin tumours for which distinction between KA and cSCC was initially clinically and pathologically challenging. The diagnosis of well-differentiated cSCCs was made and the patient was treated with surgery. Ten years after the first cSCC, he was diagnosed with Muir-Torre syndrome, a variant of Lynch syndrome, with an heterozygote mutation of the MSH2 gene. This later diagnosis allowed to screen his family members for the same mutation and to adopt an appropriate follow-up regarding the risk of digestive tumours for him and his family. Furthermore, it is important to know that, in case of non-resectable cSCC occurring in this patient, immunotherapy using anti-PD1 antibody would probably be effective due to the known increased immunogenicity of MMR deficient tumours.

Overexpression of miR-122 promotes apoptosis of dermal papilla cells by directly targeting IGF1R in androgenetic alopecia

Androgenetic alopecia (AGA) is the most common pattern of hair loss resulting from the effects of androgen on hair follicle. MicroRNAs (miRs) serve imperative roles in the regulation of many biological processes of hair follicle. However, the exact molecular mechanism of AGA remains to be elucidated. In the present study, we found miR-122, which is mainly recognized as a tumor suppressor, was highly overexpressed in the bulb of balding HFs in comparison with non-balding ones in AGA. Moreover, miR-122 induces apoptosis of human dermal papilla cells (hDPCs) with miR-122 mimics in vitro, and the expression of insulin-like growth factor 1 receptor (IGF1R) in hDPCs was reduced following upregulation of miR-122. Mechanistically, dual luciferase reporter assay confirmed that miR-122 directly targeted the 3'-untranslated region of IGF1R.These findings suggested that upregulation of miR-122 induces apoptosis, potentially via the repression of IGF1R in hDPCs of AGA, providing a novel insight into the potential pathological mechanism of miR-122 in AGA DPCs. This article is protected by copyright. All rights reserved.

Emerging Role of Dermal White Adipose Tissue in Modulating Hair Follicle Development During Aging

Hair follicle stem cells are extensively reprogrammed by the aging process, manifesting as diminished self-renewal and delayed responsiveness to activating cues, orchestrated by both intrinsic microenvironmental and extrinsic macroenvironmental regulators. Dermal white adipose tissue (dWAT) is one of the peripheral tissues directly adjacent to hair follicles (HFs) and acts as a critical macroenvironmental niche of HF. dWAT directly contributes to HF aging by paracrine signal secretion. However, the altered interrelationship between dWAT and HF with aging has not been thoroughly understood. Here, through microdissection, we separated dWAT from the skin of aged mice (18 months) and young mice (2 months) in telogen and depilation-induced anagen for transcriptome comparing. Notably, compared with young dWAT, aberrant inflammatory regulators were recapitulated in aging dWAT in telogen, including substantial overexpressed inflammatory cytokines, matrix metalloproteinases, and prostaglandin members. Nonetheless, with anagen initiation, inflammation programs were mostly abolished in aging dWAT, and instead of which, impaired collagen biosynthesis, angiogenesis, and melanin synthesis were identified. Furthermore, we confirmed the inhibitory effect on hair growth of CXCL1, one of the most significantly upregulated inflammation cytokines in aging dWAT. Besides this, we also identified the under-expressed genes related to Wnt signaling fibroblast growth factor family members and increased BMP signaling in aging dWAT, further unraveling the emerging role of dWAT in aging HFs malfunction. Finally, we proved that relieving inflammation of aging dWAT by injecting high-level veratric acid stimulated HF regenerative behavior in aged mice. Concomitantly, significantly decreased TNF-a, CCL2, IL-5, CSF2, and increased IL10 in dWAT was identified. Overall, the results elaborated on the complex physiological cycling changes of dWAT during aging, providing a basis for the potential regulatory effect of dWAT on aging HFs.

[Analysis of characteristics of collateral circulation pathways in dizziness patients caused by severe bilateral vertebral artery stenosis/occlusion]

The clinical data of 47 patients [41 males, 6 females, aged (62±7) years] treated at the Department of Neurology of the Sixth Medical Center of PLA General Hospital from October 2018 to October 2020 who were diagnosed with severe bilateral vertebral artery stenosis/occlusion through Digital Subtraction Angiography (DSA) were retrospectively collected, and the characteristics of the compensatory pathways of collateral circulation were determined. Results showed that there were 8 intracranial and extracranial compensatory pathways, with posterior communicating artery as the major type (21 cases) for intracranial ones and deep carotid artery as the major type (16 cases) for extracranial ones. As the establishment of the compensatory pathway is closely related to the lesion site, DSA assessment for patients with severe bilateral vertebral artery stenosis/occlusion is helpful for clinicians to make judgement on prognosis of patients and choose individualized treatment plans.

Transcriptome Analysis Reveals an Inhibitory Effect of Dihydrotestosterone-Treated 2D- and 3D-Cultured Dermal Papilla Cells on Hair Follicle Growth

Dermal papillae are a target of androgen action in patients with androgenic alopecia, where androgen acts on the epidermis of hair follicles in a paracrine manner. To mimic the complexity of the dermal papilla microenvironment, a better culture model of human dermal papilla cells (DPCs) is needed. Therefore, we evaluated the inhibitory effect of dihydrotestosterone (DHT)-treated two-dimensional (2D)- and 3D-cultured DPCs on hair follicle growth. 2D- and 3D-cultured DPC proliferation was inhibited after co-culturing with outer root sheath (ORS) cells under DHT treatment. Moreover, gene expression levels of β-catenin and neural cell adhesion molecules were significantly decreased and those of cleaved caspase-3 significantly increased in 2D- and 3D-cultured DPCs with increasing DHT concentrations. ORS cell proliferation also significantly increased after co-culturing in the control-3D model compared with the control-2D model. Ki67 downregulation and cleaved caspase-3 upregulation in DHT-treated 2D and 3D groups significantly inhibited ORS cell proliferation. Sequencing showed an increase in the expression of genes related to extracellular matrix synthesis in the 3D model group. Additionally, the top 10 hub genes were identified, and the expression of nine chemokine-related genes in DHT-treated DPCs was found to be significantly increased. We also identified the interactions between transcription factor (TF) genes and microRNAs (miRNAs) with hub genes and the TF-miRNA coregulatory network. Overall, the findings indicate that 3D-cultured DPCs are more representative of in vivo conditions than 2D-cultured DPCs and contribute to our understanding of the molecular mechanisms underlying androgen-induced alopecia.

Recent Progress in the Understanding of the Effect of Sympathetic Nerves on Hair Follicle Growth

Clinical observation and experimental studies have long suggested that the perifollicular nerves have nutritional and regulatory effects on the growth, development, and physiological cycle of hair follicles (HFs), even though the concrete mechanism remains obscure. Recently, with the progress of immunohistochemistry and molecular biology techniques, more innovation has been made in the study of the follicular sympathetic nerves and its nerve-effect factor norepinephrine affecting hair follicle stem cells. This review highlights the progress in the regulation of the sympathetic nervous system toward the growth of HFs.

A three-dimensional bioprinting technique, based on a gelatin/alginate hydrogel, for the tissue engineering of hair follicle reconstruction

Hair loss remains a challenging clinical problem that influences the quality of life. Three-dimensional (3D) bioprinting has become a valuable tool for fabricating tissue constructs for transplantation and other biomedical applications. Although some simple organs, such as skin and cartilage, have been successfully simulated, it remains challenging to make hair follicles (HFs), which are highly complex organs. The tissue engineering of human HFs has been a long-standing challenge, and progress with this has lagged behind that with other lab-grown tissues. This is principally due to a lack of availability of a platform that can successfully recapitulate the microenvironmental cues required to maintain the requisite cellular interactions for hair neogenesis. In this study, we used a 3D bioprinting technique based on a gelatin/alginate hydrogel to construct a multilayer composite scaffold with cuticular and corium layers to simulate the microenvironment of dermal papilla cells (DPCs) in the human body. This new approach permits the controllable formation of self-aggregating spheroids of DPCs in a physiologically relevant extracellular matrix and the initiation of epidermal-mesenchymal interactions, which results in HF formation in vivo. In conclusion, our 3D-bioprinted multilayer composite scaffold prepared using a gelatin/alginate hydrogel provides a suitable 3D microenvironment for DPCs to induce HF formation. The ability to regenerate entire HFs should have a significant impact on the medical management of hair loss. This method may also have critical applications for skin tissue engineering, with its appendages, for other purposes.

[Collateral circulation pathway in patients with basilar artery occlusion/severe stenosis: a single-center case series]

Objective: To investigate the collateral circulation compensation model in patients with favorable prognosis of basilar artery occlusion/severe stenosis treated with drugs or endovascular therapy. Methods: Clinical data of patients with basilar artery occlusion/severe stenosis and good clinical outcome were retrospectively collected in the Department of Neurology, Sixth Medical Center of PLA General Hospital from January 2019 to January 2020. They were divided into intensive drug therapy group and combined endovascular therapy group. The number and ways of collateral compensation pathway described by digital substraction angiography (DSA) were analyzed, and the characteristics of the collateral compensation model were summarized. SPSS22.0 software was used for statistical analysis, and the constituent ratio (%) was used for statistical description of the enumeration data. Results: A total of 32 eligible patients were included, including 27 males and 5 females, with an average age 45-76 (59±10) years. The compensation model included posterior communicating artery-posterior cerebral artery (13 cases, 40.6%), posterior communicating artery-posterior cerebral artery-basilar artery (10 cases, 31.2%), cerebellar artery-anastomotic branches of superior cerebellar artery (8 cases, 25.0%), anterior choroid artery-anastomotic branches of posterior choroid artery (2 cases, 6.2%), collateral circulation not established (11 cases, 34.4%).In drug treatment group, collateral compensation was found in the majority (14/15), with mainly posterior communicating artery (10/14).Most patients in combined treatment group did not develop collateral compensation (10/17), anastomotic branches of PICA-SCA were the main routes (6/7). Conclusion: In patients with basilar artery occlusion/severe stenosis, favorable clinical outcome can be achieved in both groups of patients treated with intensive drug therapy or endovascular therapy.

[Inhibition of mitochondrial reactive oxygen species reduces high glucose-induced pyroptosis and ferroptosis in H9C2 cardiac myocytes]

OBJECTIVE

To observe the effect of inhibiting mitochondrial oxidative stress and NLRP3 inflammasomes on high glucose (HG)-induced pyroptosis and ferroptosis in H9C2 cardiac muscle cells and explore the possible interactions between mitochondrial reactive oxygen species (ROS) and inflammasomes.

METHODS

H9C2 cells exposed to high glucose (35 mmol/L) were treated with the mitochondrial antioxidant mitoquinone (MitoQ), the NLRP3 antagonist MCC950, or both MCC950 and rotenone (a mitochondrial electron transport antagonist), and the cell viability was measured with CCK-8 assay. The cellular and mitochondrial ROS levels were measured using CellRox and Mitosox fluorescent probes, respectively. The cellular NLRP3 inflammasome level was detected with immunofluorescence assay, and the expressions of the key proteins related with pyroptosis and ferroptosis were determined with Western blotting.

RESULTS

HG exposure significantly lowered the viability of H9C2 cells (P < 0.01), reduced the expression of GPX4 protein (a key protein related with ferroptosis) (P < 0.01), and increased the fluorescence intensities of NLRP3 (P < 0.01) and ROS (at both the cellular and mitochondrial levels, P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.01). Treatment with either MitoQ or MCC950 significantly increased the viability of HG-exposed cells (P < 0.01), increased GPX4 expression (P < 0.01), and reduced the fluorescence intensities of NLRP3 (P < 0.01) and cellular and mitochondrial ROS (P < 0.01) and the protein expressions of NLRP3 and GSDMD-NT (P < 0.05). Compared with MCC950 treatment, treatment with both MCC950 and rotenone significantly reduced the viability of HG-exposed cells (P < 0.01), lowered GPX4 expression (P < 0.01), and increased the fluorescence intensities of ROS and NLRP3 (P < 0.01) and the protein levels of NLRP3 and GSDMD-NT (P < 0.05).

CONCLUSION

MitoQ inhibits mitochondrial ROS production to reduce HGinduced NLRP3 inflammasome activation and thus suppress pyroptosis and ferroptosis of cardiac muscle cells. There may be an interaction between mitochondrial ROS and NLRP3 inflammasomes.

[Application of left-sided uncinate process first approach in pancreaticoduodenectomy]

Objective: To evaluate the value of left-sided uncinate process first approach in pancreaticoduodenectomy. Methods: The clinical data of 152 patients who underwent the left-sided uncinate process first approach during pancreaticoduodenectomy at Pancreas Center, the First Affiliated Hospital of Nanjing Medical University from January 2020 to December 2020 were analyzed retrospectively. There were 64 females and 88 males,with age(M(Q_R)) of 62.0(14.7)years(range:16.0 to 84.0 years). The clinical date of 117 patients who underwent pancreaticoduodenectomy without using left-sided uncinate process first approach in the same period was selected as the control group,including 65 females and 52 males,with age of 64.0(13.0) years(range:13.0 to 84.0 years). Fisher exact probability method and t test were used to compare the data between the two groups,rank sum test was used for comparison of continuous variables between the two groups. Results: Pancreaticoduodenectomy was successfully performed in 152 patients in left-sided uncinate process first approach group. The operation time was 222.5(77.0) minutes(range:117.0 to 480.0 minutes),the time of uncinate process resection from left-side(the time from jejunum dissection to complete dissociation of the uncinate process) was 11.0(4.5) minutes(range:7.5 to 20.0 minutes),the time of pancreatic head resection (the time from jejunum dissection to pancreaticoduodenal specimen removal) was 26.0(8.5) minutes(range:20.0 to 41.0 minutes),the intraoperative blood loss was 200(150) ml(range:50 to 800 ml),and the intraoperative blood transfusion rate was 9.2% (14/152). Postoperative conditions:The postoperative hospital stay was 12 (9) d(range:6 to 55 d),the overall incidence of postoperative complications was 59.9%(91/152),and there was no perioperative death. Pathological results:The R0 resection rate of periampullary malignant tumor was 64.3%(77/112),with negative rate of uncinate process margin was 91.1%(102/112). The R0 resection rate of pancreatic ductal adenocarcinoma was 46.9%,with negative rate of uncinate process margin was 89.1%(57/64). Compared with the non-left-sided uncinate process first approach group(222.5(77.0) minutes, 9.2%(14/152)),the left-sided uncinate process first approach group had shorter operation time(246.0(94.0) minutes) (Z=3.964,P<0.01),less intraoperative blood loss (18.8%(22/117))(Z=4.843,P<0.01),and lower intraoperative blood transfusion rate(χ²=5.248,P=0.029). However,there were no significant differences between two groups in postoperative hospital stay(Z=1.682,P=0.093),postoperative overall complications(P=0.549),R0 resection rate of periampullary malignant tumor(χ²=2.012,P=0.156),and negative rate of uncinate process margin(χ²=2.108,P=0.147). Conclusions: The "left-sided uncinate process first approach" could completely resect uncinate process under a direct vision,especially when the uncinate process was behind the superior mesenteric artery or beyond the left lateral margin of the superior mesenteric artery. The "left-sided uncinate process first approach" might increase the negative rate of uncinate process margin and R0 resection rate for periampullary malignant tumor.

Effect of De-epithelialization on Graft Survival Rate After Follicular Unit Extraction

BACKGROUND

To achieve a natural postoperative appearance, hair grafts are often de-epithelialized from the epidermis during follicular unit extraction (FUE). However, the effect of de-epithelialization on the survival rate of transplanted hair follicles (HFs) has not been investigated.

OBJECTIVE

To investigate the effect of de-epithelialization on the survival rate of transplanted HFs.

METHODS

A total of 64 male patients with androgenetic alopecia were included in this study. They were randomly divided into de-epithelialization and control groups. Organ culture was performed to assess the elongation of hair shaft and the percentage of anagen HFs in both groups. Patients were followed up postoperatively to evaluate complications, postoperative shedding, survival rates, and satisfaction.

RESULTS

No significant difference in hair shaft elongation and percentage of anagen HFs was observed between both groups. The immediate postoperative satisfaction in the control group was much lower than that in the de-epithelialization group (71.25% and 100%, respectively). No significant differences in shedding rate, graft survival rate, and complications were noticed between both groups.

CONCLUSION

Follicular de-epithelialization does not affect the survival rate of graft in FUE. Based on these data, de-epithelialization may improve immediate postoperative appearance and lead to a more pleasing cosmetic outcome.

LncRNA RPPH1 predicts poor prognosis and regulates cell proliferation and migration by repressing P21 expression in gastric cancer

OBJECTIVE

The purpose of this study was to explore the expression and biological functions of long non-coding ribonucleic acid (lncRNA) ribonuclease P RNA component H1 (RPPH1) in gastric cancer (GC), and to analyze the correlations of lncRNA expression with the clinical features and prognosis of GC patients.

PATIENTS AND METHODS

The relative expression of RPPH1 in tissue specimens from 60 GC patients was measured via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR), and the correlations of RPPH1 expression with tumor-node-metastasis (TNM) stage, lymph node metastasis, etc. in GC patients were analyzed. Then, qRT-PCR was performed to detect the relative expression level of RPPH1 in GC cells. Moreover, colony formation assay, 5-Ethynyl-2'-deoxyuridine (EdU) staining, wound-healing assay, and transwell assay were employed to investigate the influence of RPPH1 on GC cell functions. After interfering in the expression of RPPH1, the changes in p21 (CDKN1A, cyclin dependent kinase inhibitor 1A) expression were determined through qRT-PCR and Western blotting.

RESULTS

It was shown in qRT-PCR assay results that the expression of RPPH1 was upregulated in 60 cases of GC tissues. Statistical analysis revealed that RPPH1 expression was positively correlated with the TNM stage, lymph node metastasis, and infiltration depth in GC patients. Besides, highly expressed lncRNA RPPH1 suggested poor prognosis of GC patients. Based on the results of qRT-PCR assay, the expression of RPPH1 in GC cells was upregulated. After interfering in RPPH1 expression, both colony formation assay and EdU staining indicated that the proliferative capacity of GC cells was repressed. Furthermore, it was manifested in the results of wound-healing and transwell assays that the migratory and invasive abilities of GC cells were weakened. Finally, the qRT-PCR and Western blotting assay results demonstrated that p21 expression was upregulated after interfering in the expression of RPPH1 in GC cells.

CONCLUSIONS

The expression of lncRNA RPPH1 is upregulated in GC, suggesting that the prognosis of the patients is poor. Highly expressed RPPH1 promotes the proliferation and metastasis of GC cells by regulating p21 expression.