Sirtuin 3 regulates mouse pancreatic beta cell function and is suppressed in pancreatic islets isolated from human type 2 diabetic patients

Aims/hypothesis

Sirtuin (SIRT)3 is a mitochondrial protein deacetylase that regulates reactive oxygen species (ROS) production and exerts anti-inflammatory effects. As chronic inflammation and mitochondrial dysfunction are key factors mediating pancreatic beta cell impairment in type 2 diabetes, we investigated the role of SIRT3 in the maintenance of beta cell function and mass in type 2 diabetes.

Methods

We analysed changes in SIRT3 expression in experimental models of type 2 diabetes and in human islets isolated from type 2 diabetic patients. We also determined the effects of SIRT3 knockdown on beta cell function and mass in INS1 cells.

Results

SIRT3 expression was markedly decreased in islets isolated from type 2 diabetes patients, as well as in mouse islets or INS1 cells incubated with IL1β and TNFα. SIRT3 knockdown in INS1 cells resulted in lowered insulin secretion, increased beta cell apoptosis and reduced expression of key beta cell genes. SIRT3 knockdown also blocked the protective effects of nicotinamide mononucleotide on pro-inflammatory cytokines in beta cells. The deleterious effects of SIRT3 knockdown were mediated by increased levels of cellular ROS and IL1β.

Conclusions/interpretation

Decreased beta cell SIRT3 levels could be a key step in the onset of beta cell dysfunction, occurring via abnormal elevation of ROS levels and amplification of beta cell IL1β synthesis. Strategies to increase the activity or levels of SIRT3 could generate attractive therapies for type 2 diabetes.     

Living conditions of children at risk for noma: Nigerian experience

The study reported in this paper was carried out in the Northwestern and Southwestern regions of Nigeria, between October 1996 and April 1998. The study examined the possible contributory role of living conditions in the development of acute necrotizing gingivitis (ANG) or noma from oral lesions. Questionnaire data obtained from 42 fresh noma cases seen in the Northwest and four fresh cases seen in the Southwest were examined. In addition 46 cases of advanced ANG from the Southwest were included. The main focus was to compare some of the environmental living conditions of cases with advanced ANG and those with noma in these regions. All the noma and ANG cases were seen in children aged 2-12 years. The level of good oral hygiene practices and general environmental living conditions were significantly higher in the Southwest than in the Northwest. Data also showed that living in close proximity with livestock was significantly higher in the Northwest than in the Southwest (P < 0.05). The environmental living conditions of children in the Northwest were further compounded by poor sanitary faecal disposal practices as well as minimal access to potable water. The overall data indicated that living in substandard accommodations, exposure to debilitating childhood diseases, living in close proximity to livestock, poor oral hygiene, limited access to potable water and poor sanitary disposal of human and animal faecal waste could have put the children in the Northwest at higher risk for noma than the children in the Southwest. These could have been responsible for the higher prevalence of noma in the Northwest than in the Southwest.     

Generation of tyrosine hydroxylase-producing neurons from precursors of the embryonic and adult forebrain

We have explored the plastic ability of neuronal precursors to acquire different identities by manipulating their surrounding environment. Specifically, we sought to identify potential signals involved in the specification of forebrain dopaminergic neurons. Here we describe culture conditions under which tyrosine hydroxylase (TH) expression is induced in neuronal precursors, which were derived directly from the embryonic striatum and adult subependyma (SE) of the lateral ventricle or generated from multipotent forebrain stem cells. TH was successfully induced in all of these cell types by 24 hr exposure to basic fibroblast growth factor (FGF2) and glial cell conditioned media (CM). The greatest magnitude of the inductive action was on embryonic striatal precursors. Although FGF2 alone induced limited TH expression in striatal cells (1.1 +/- 0.2% of neurons), these actions were potentiated 17.5-fold (19.6 +/- 1.5% of neurons) when FGF2 was coadministered with B49 glial cell line CM. Of these TH-immunoreactive cells, approximately 15% incorporated bromodeoxyuridine (BrdU), indicating that they were newly generated, and 95% coexpressed the neurotransmitter GABA. To investigate whether precursors of the adult forebrain subependyma were competent to respond to the instructive actions of FGF2+CM, they were first labeled in vivo with a pulse of BrdU. Although none of the cells expressed TH in control, 0.2% of total cells showed TH immunoreactivity in FGF2+CM-treated cultures. Under these same conditions only, in vitro-generated precursors from epidermal growth factor-responsive stem cells exhibited TH expression in 10% of their total neuronal progeny. Regulation of neurotransmitter phenotype in forebrain neuronal precursors, by the synergistic action of FGF2 and glial-derived diffusible factors, may represent a first step in understanding how these cells are generated in the embryonic and adult brain and opens the prospect for their manipulation in vitro and in vivo for therapeutic use.     

Eruptive syringomas: Summary of ninety cases and a brief literature review

Background

Eruptive syringomas is a rare variant of syringoma, which is a benign adenoma differentiated from the terminal ducts of the eccrine glands. Nowadays, it's widely valued because of obvious skin lesions, large scope of influence, and high misdiagnosis rate.

Objectives

We aim to explore the clinical features of eruptive syringomas and the current research progress.

Materials and Methods

We firstly summarized the clinical features of 90 cases of eruptive syringomas. Then, the chi-square test was used to analyze the relationship between the onset site of eruptive syringomas and age, as well as gender. Finally, we briefly reviewed the previous literature.

Results

During 12 years, 90 cases of eruptive syringomas were diagnosed in our hospital, including 28 males (31.1%) and 62 females (68.9%). The average diagnosed age was 28.8. Patients from 20 to 40 years old is 63 (70%), which is the most. 60 (66.7%) patients had the course for more than 1 year. Among onset sites, the neck, chest, and abdomen were in the top three. The chi-square test showed that there were no significant differences in the onset sites of patients aged ≤ 20 and >20 years old (p-value = 0.181), as well as male and female (p-value = 0.363).

Conclusion

We found that more female than male was affected, and the most common onset sites were the neck, chest, and abdomen. Neither age nor gender was significantly associated with onset site distribution. Our study provides some data support for the research of eruptive syringomas.     

Effects of mesotherapy introduction of compound glycyrrhizin injection on the treatment of moderate to severe acne

Background

Compound glycyrrhizin has achieved outstanding results in the treatment of various skin diseases. However, the use of mesotherapy to inject compound glycyrrhizin into the skin to treat acne is still understudied.

Aims

This paper aims to explore the effects of mesotherapy introduction of compound glycyrrhizin injection on the acne.

Materials & Methods

A total of 108 patients were included in this study and divided into the control group (n = 54) and the observation group (n = 54). The control group was treated with topical clindamycin gel, while the study group was treated with topical clindamycin gel + mesotherapy and compound glycyrrhizin injection. Skin transepidermal water loss (TEWL), cuticle water content, acne severity, adverse reactions, and inflammatory reactions were documented before and after treatment in the two groups.

Results

The usage of mesotherapy to inject compound glycyrrhizin into the skin of acne patients more effectively treat acne than traditional clindamycin gel. The mesotherapy compound glycyrrhizin can more effectively protect the skin barrier of patients and reduce the loss of skin moisture. Compared with the traditional clindamycin gel, the combination of mesotherapy and compound glycyrrhizin more effectively inhibit the inflammatory reaction in acne patients and reduce skin damage in acne patients.

Discussion/Conclusion

Mesoderm introduction of compound glycyrrhizin injection has better effects on the treatment of moderate to severe acne than clindamycin gel.     

Metabolic profiles in plasma of patients with herpes labialis based on GC–MS

Objective

This study aims to compare the plasma metabolic profiles of patients with herpes labialis with healthy controls and identify the biomarkers of herpes labialis.

Subjects and Methods

We collected 18 patients with herpes labialis and 20 healthy individuals. Plasma samples from both groups were analyzed using gas chromatography–mass spectrometry (GC–MS).

Results

According to the principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), we found that metabolic profiles had changed in patients with herpes labialis compared to the controls. By further selecting the different metabolites according to the variable importance in the projection (VIP) and p valve of t-tests, we found that acetic acid, pyroglutamic acid, alanine, ethanedioic acid, cyclohexaneacetic acid, pyruvic acid, d-mannose, phosphoric acid, l-amphetamine, and citric acid were decreased in patients with herpes labialis, while sedoheptulose and ethylamine were increased. Pathway analysis showed that herpes labialis may affect the amino acid and energy metabolism.

Conclusions

Our findings may contribute to elucidating the metabolic basis of herpes labialis and provide a new perspective for further research on the “Shang-Huo” state in traditional Chinese medicine (TCM).