Ablation of Liver X receptor β in mice leads to overactive macrophages and death of spiral ganglion neurons

Age-related hearing loss is the most common type of hearing impairment, and is typically characterized by the loss of spiral ganglion neurons (SGNs). The two Liver X receptors (LXRs) are oxysterol-activated nuclear receptors which in adults, regulate genes involved in cholesterol homeostasis and modulation of macrophage activity. LXRβ plays a key role in maintenance of health of dopaminergic neurons in the substantia nigra, large motor neurons in the spinal cord, and retinal ganglion cells in adult mice. We now report that LXRβ is expressed in the SGNs of the cochlea and that loss of LXRβ leads to age-related cochlea degeneration. We found that in the cochlea of LXRβ-/- mice, there is loss of SGNs, activation of macrophages, demyelination in the spiral ganglion, decrease in glutamine synthetase (GS) expression and increase in glutamate accumulation in the cochlea. Part of the cause of damage to the SGNs might be glutamate toxicity which is known to be very toxic to these cells. Our study provides a so far unreported role of LXRβ in maintenance of SGNs whose loss is a very common cause of hearing impairment.

[Clinical outcomes analysis of fertility-preserving therapy for atypical endometrial hyperplasia and early endometrial carcinoma]

Objective: To analyze the clinical efficacy of fertility-preserving therapy in patients with atypical endometrial hyperplasia (AEH) and early endometrial carcinoma (EC). Methods: The general condition, pathological type, treatment plan, tumor outcomes and pregnancy outcomes of 110 patients with AEH and EC treated with fertility-preserving therapy in Peking University People's Hospital from December 2005 to September 2019 were retrospectively analyzed. Kaplan-Meier and Log rank tests were used for survival analysis. Results: The response rate of 110 cases of AEH (62 cases) and EC (48 cases) was 94.5% (104/110) after fertility-preserving therapy. There were 93 cases (84.5%) achieved complete response and 11 cases (10.0%) achieved partial response, and the recurrence rate was 29.0% (27/93). The complete response rates of AEH and EC were 90.3% (56/62) and 77.1% (37/48), respectively, without significant difference (P=0.057). The recurrence rates of EC were significantly higher than that of AEH (40.5% vs 21.4%; P=0.022). Forty-one patients with complete response had pregnancy intention, the pregnancy rate was 70.7% (29/41), and the live birth rate was 56.1% (23/41). The live birth rate of AEH was 68.2% (15/22) and that of EC was 42.1% (8/19), the difference was statistically significant (P=0.032). The pathological type was related with the recurrence (P=0.044). Conclusions: Patients with AEH and EC can obtain high complete response rate and pregnancy rate after fertility-preserving therapy. The recurrence rate of EC is higher than that of AEH, while the live birth rate of AEH is higher than that of EC.

[Application and clinical significance of TCGA molecular classification in endometrial cancer]

Objective: To explore the application and clinical significance of the cancer genome atlas (TCGA) molecular classification in endometrial cancer (EC). Methods: Sixty-six EC patients collected from December 2018 to March 2021 from Peking University People's Hospital were categorized into four subgroups based on TCGA molecular classification tested by next generation sequencing. The correlation among four molecular subgroups and the clinical-pathological features including prognosis were analyzed. Results: (1) Clinical and pathological features: median age at diagnosis was 56 years (range: 24-78 years). The cases were distributed as follows: 3 (5%) cases DNA polymerase epsilon (POLE) ultra-mutated, 11 (17%) cases high microsatellite instability (MSI-H) including 2 Lynch syndrome, 42 (64%) cases low copy-number (CN-L) and 10 (15%) cases high copy-number (CN-H). There were significant differences among four subtypes in the combination of other tumors, tumor family history, surgical method, International Federation of Gynecology and Obstetrics (FIGO, 2009) stage, depth of muscle invasion and lymph vascular space invasion (all P<0.05). The proportions of patients in CN-H subgroup with advanced FIGO stage (stage Ⅲ-Ⅳ), deep muscle invasion and positive lymph-vascular space invasion were significantly increased. There were no significant differences in age, menopausal status, body mass index, metabolic syndrome-related complications, preoperative serum CA₁₂₅ and human epididymis protein 4 levels, tumor size, pathological grade (only endometrioid cancer), and lymph node metastasis among the 4 TCGA molecular types (all P>0.05). (2) Immuno-related molecular analysis: among 66 EC patients, 27 patients underwent immunohistochemical analysis of programmed cell death 1 ligand 1 (PD-L1) protein, and 28 patients underwent tumor mutation burden (TMB) detection. POLE and MSI-H subgroups contained TMB than those in CN-L and CN-H (P<0.05).(3) Prognosis: the median follow-up time was 10 months (range: 0-28 months). The progression-free survival rate of TCGA molecular types were 100% (POLE ultra-mutated), 100% (MSI-H), 98% (CN-L), and 80% (CN-H) respectively and had significant differences (P=0.034). The overall survival were 100% (POLE ultra-mutated), 100% (MSI-H), 98% (CN-L), and 90% (CN-H) respectively, but there were not statistically significant difference (P=0.361). POLE ultra-mutated and MSI-H subgroups had the best survival, while CN-H had the worst. Conclusion: TCGA molecular classification has feasibility and clinical value in clinical application of EC, which is helpful to identify the prognosis of patients.

[Correlation between the primary tumor size of endometrial carcinoma and lymph node metastasis and recurrence]

Objective: To investigate the clinical significance of the primary tumor size in patients with endometrial carcinoma (EC). Methods: A total of 385 patients with EC admitted to Peking University People's Hospital from January 2006 to December 2016 with complete follow up data were selected, whose tumor size data before biopsy were retrospectively studied. Results: (1) The mean diameter of the primary tumor was (3.6±1.8) cm (range: 1-15 cm). And 48 cases were 0-<2 cm, 78 cases were 2-<3 cm, 92 cases were 3-<4 cm, 73 cases were 4-<5 cm, 94 cases were ≥5 cm. The diameter of the tumor was associated with age <60 years old, premenopause, CA₁₂₅≥35 kU/L, non-parturition, poor differentiation, stage Ⅲ-Ⅳ, depth of myometrial infiltration ≥1/2, cervical interstitial involvement, adnexal metastasis and lymph node metastasis (all P<0.05), but not associated with body mass index, hypertension, diabetes mellitus, pathology, lymph-vascular space invasion (all P>0.05). (2) Among the 334 patients underwent lymphadenectomy, 45 (13.5%, 45/334) cases with lymph node metastasis were observed. Stratified analysis showed that lymph node metastasis and recurrence rate of patients with EC gradually increased with the increase of tumor size (P<0.05). Adopting 2, 3, 4 and 5 cm as cut-off values of tumor size, there were significant differences in the rate of lymph node metastasis and recurrence among them observed (P<0.05), except for lymph node metastasis rate and recurrence rate when the cut-off value was 2 cm (P>0.05). (3) An receiver operating characteristic (ROC) curve analysis showed that a tumor diameter of 4.25 cm was the cut-off prognostic value to predict lymph node metastasis and recurrence of EC. Conclusions: Tumor diameter is significantly correlated with lymph node metastasis and recurrence in patients with EC. Tumor size should be considered in determining the scope of surgery and adjuvant therapy.

Expression and localization of retinoid receptors in the testis of normal and infertile men

Retinoic acid (RA), the active metabolite of vitamin A, is one of the most important factors regulating spermatogenesis. RA activates downstream pathways through its receptors (retinoic acid receptor alpha [RARA], retinoic acid receptor beta, and retinoic acid receptor gamma [RARG]) and retinoid X receptors (retinoid X receptor alpha [RXRA], retinoid X receptor beta [RXRB], and retinoid X receptor gamma [RXRG]). These receptors may serve as therapeutic targets for infertile men. However, the localization and expression of retinoid receptors in normal and infertile men were unknown. In this study, we found RARA and RARG were mostly localized in spermatocytes and round spermatids, RXRB was mainly expressed in Sertoli cells, and RXRG was expressed in most cell types in the fertile human testis. The localization of RARA, RARG, RXRB, and RXRG in men with hypospermatogenesis (HYPO) was similar to that of men with normal fertility. In addition, the messenger RNA expression levels of RARA, RARG, RXRA, RXRB, and RXRG were significantly decreased in men with Sertoli cell-only syndrome (SCOS) and maturational arrest (MA), but not in men with HYPO. These results suggest that reduced levels of RARA, RARG, RXRB, RXRA, and RXRG are more closely associated with SCOS and MA spermatogenetic failure. These results could contribute to the development of new molecular indicators of spermatogenic dysfunction and might provide novel therapeutic targets for treating male infertility.

Liver X receptor α induces 17β-hydroxysteroid dehydrogenase-13 expression through SREBP-1c

Liver X receptors, including LXRα and LXRβ, are known to be master regulators of liver lipid metabolism. Activation of LXRα increases hepatic lipid storage in lipid droplets (LDs). 17β-Hydroxysteroid dehydrogenase-13 (17β-HSD13), a recently identified liver-specific LD-associated protein, has been reported to be involved in the development of nonalcoholic fatty liver disease. However, little is known about its transcriptional regulation. In the present study, we aimed at determining whether 17β-HSD13 gene transcription is controlled by LXRs. We found that treatment with T0901317, a nonspecific LXR agonist, increased both 17β-HSD13 mRNA and protein levels in cultured hepatocytes. It also significantly upregulated hepatic 17β-HSD13 expression in wild-type (WT) and LXRβ^-/- mice but not in LXRα^-/- mice. Basal expression of 17β-HSD13 in the livers of LXRα^-/- mice was lower than that in the livers of WT and LXRβ^-/- mice. Moreover, induction of hepatic 17β-HSD13 expression by T0901317 was almost completely abolished in SREBP-1c^-/- mice. Bioinformatics analysis revealed a consensus sterol regulatory element (SRE)-binding site in the promoter region of the 17β-HSD13 gene. A 17β-HSD13 gene promoter-driven luciferase reporter and ChIP assays further confirmed that the 17β-HSD13 gene was under direct control of SREBP-1c. Collectively, these findings demonstrate that LXRα activation induces 17β-HSD13 expression in a SREBP-1c-dependent manner. 17β-HSD13 may be involved in the development of LXRα-mediated fatty liver.

An ERβ agonist induces browning of subcutaneous abdominal fat pad in obese female mice

Estrogen, via estrogen receptor alpha (ERα), exerts several beneficial effects on metabolism and energy homeostasis by controlling size, enzymatic activity and hormonal content of adipose tissue. The actions of estrogen on sympathetic ganglia, which are key players in the browning process, are less well known. In the present study we show that ERβ influences browning of subcutaneous adipose tissue (SAT) via its actions both on sympathetic ganglia and on the SAT itself. A 3-day-treatment with a selective ERβ agonist, LY3201, induced browning of SAT in 1-year-old obese WT and ERα^−/− female mice. Browning was associated with increased expression of ERβ in the nuclei of neurons in the sympathetic ganglia, increase in tyrosine hydroxylase in both nerve terminals in the SAT and sympathetic ganglia neurons and an increase of β3-adrenoceptor in the SAT. LY3201 had no effect on browning in young female or male mice. In the case of young females browning was already maximal while in males there was very little expression of ERβ in the SAT and very little expression of the β3-adrenoceptor. The increase in both sympathetic tone and responsiveness of adipocytes to catecholamines reveals a novel role for ERβ in controlling browning of adipose tissue.

729G/C polymorphism in Toll-like receptor 4 results in increased susceptibility to bladder cancer

In this study, the association between the 729G/C polymorphism in Toll-like receptor 4 (TLR4) and the risk of bladder cancer was investigated. A total of 376 patients with bladder cancer and 380 healthy volunteers from the Third Xiangya Hospital of Central South University (China) were enrolled in this study between January 2008 and February 2014. The TLR4-729G/C polymorphism was detected by the polymerase chain reaction-restriction fragment length polymorphism assay. There was a significant difference in the distribution of the TLR4-729G/C genotype between bladder cancer patients and healthy controls (P < 0.001). Our analysis showed that the GC genotype (OR = 2.99; 95%CI = 1.01-4.81, P = 0.046) and CC genotype (OR = 3.67; 95%CI = 2.11-7.27, P = 0.017) were significantly associated with increased bladder cancer risk when the GG genotype served as a reference. Furthermore, carriers of the C allele had a significantly increased risk of developing bladder cancer (OR = 3.89; 95%CI = 2.88-8.53; P = 0.009). Our results suggest a correlation between the TLR4-729G/C polymorphism and the risk of developing bladder cancer in this Chinese population.

The Value of Proton Magnetic Resonance Spectroscopy in High-Intensity Focused Ultrasound Treatment of Experimental Liver Cancer

High-intensity focused ultrasound (HIFU) is a rapidly developing, non-invasive technique for local treatment of solid tumors that produce coagulative tumor necrosis. This study is aimed to investigate the feasibility of proton magnetic resonance spectroscopy (MRS) on early assessing treatment of HIFU ablation in rabbit with VX2 liver tumor. HIFU ablation was performed on normal liver and VX2 tumor in rabbit, and MRS was performed on normal liver and VX2 tumor before and 2 days after 100% HIFU ablation or 80% ablation in tumor volume. Choline (Cho) and choline/lipid (Cho/Lip) ratios between complete and partial HIFU ablation of tumor were compared. Tissues were harvested and sequentially sliced to confirm the necrosis. In normal liver, the Cho value liver was not obviously changed after HIFU (P > .05), but the Cho/Lip ratio was decreased (P < .05). Cho in liver VX2 tumor was much higher than that in normal liver (P < .001). Cho and Cho/Lip ratio were significantly decreased in tumor after complete HIFU ablation and partial HIFU ablation, and the Cho value in complete HIFU tumor ablation did not show any difference from that in normal liver after HIFU (P > .05); however, the Cho value in partial ablation was still higher than that in normal liver before or in tumor after complete HIFU treatment due to the residual part of tumors, and Cho/Lip ratio is lower than that in complete HIFU treatment (P < .001). The changes in MRS parameters were consistent with histopathologic changes of the tumor tissues after treatment. MRS could differentiate the complete tumor necrosis from residual tumor tissue, when combined with magnetic resonance imaging. We conclude that MRS may be applied as an important, non-invasive biomarker for monitoring the thoroughness of HIFU ablation.

Pathogenic effects of the coccidium Eimeria ninakohlyakimovae in goats

Twenty-four coccidia-free goats were reared artificially in indoor cages and allocated to 6 groups of 4 animals each. At 20 days of age, goats in groups 1-3 received 10(4),10(5) and 10(6) sporulated oocysts of Eimeria ninakohlyakimovae per goat, respectively, each as a single dose. Goats in group 4 received daily doses increasing over a 3-week period, starting with 100/day for the first week, followed by 1000, and 10,000/day in weeks 2, 3, respectively. Goats in group 5 received 10(4) oocysts following a challenge dose of 10(6) oocysts on day 32. Goats in group 6 were kept as uninoculated controls. Infected animals showed diarrhoea and weight loss. Goats in group 4 showed longer periods of diarrhoea and patency than other infected goats. Goats in group 5 showed the same severe clinical signs as those in group 3 but produced very low oocyst output after a challenge dose. The diarrhoea was associated with a reduction in alkaline phosphatase activity and increases in packed cell volume and haemoglobin. No significant differences were found in serum aspartate aminotransferase, alanine aminotransferase, total protein, albumin, globulin, Na+, K+,Cl- between groups during 48 days after inoculation. There were no serum enzyme indications of damage to the liver. Histological examination performed 100 days after inoculation revealed that inoculated goats had mild subacute to chronic proliferative enteritis in the lower small intestine and the large intestine, and the mesenteric lymph nodes, gallbladders and livers also showed slight histological lesions. The results showed that E. ninakohlyakimovae was highly pathogenic.

[The effect of needleless electroacupuncture in general anesthesia during laparoscopic surgery]

BACKGROUND

Three kinds of pain-relieving substances, namely, endorphins, enkephalins and dynorphins, can be released by stimulating the relevant acupoints with the dense-disperse mode of nerve stimulator. The neurochemical mechanisms of pain relief by acupoint stimulation have been widely studied and proved. In the present study, we investigated the modulatory effect of needleless electroacupuncture on the inhaled general anesthesia during laparoscopic surgery.

METHODS

Forty gynecologic patients of ASA class I-II status, scheduled for elective laparoscopic surgery, were randomly allocated to study and control groups. Induction and intubation were performed in the same fashion and anesthesia was maintained with inhaled general anesthetics: 50% N2O in oxygen and isoflurane, which was adjusted to keep the hemodynamic changes within +/- 10% of their preoperated level. HANS (LY 257), a special nerve stimulator with 2 Hz and 100 Hz dense-disperse wave, was used to stimulate the bilateral Yang Ling Chuan (G34), Zusanli (S36) acupoints in patients of the study group during the surgery.

RESULTS

We found that needleless electroacupuncture significantly lowered the volume concentration of isoflurane from 1.0 +/- 0.33% to 0.74 +/- 0.19% (p < 0.05) at 30 min after the start of operation. Furthermore, it also significantly shortened the recovery time from 11.4 +/- 3.3 min to 8.8 +/- 3.2 min (p < 0.05).

CONCLUSIONS

Under general anesthesia, the application of needleless electroacupuncture can reduce the volume concentration of isoflurane and shorten the post-anesthetic recovery time during laparoscopic surgery.

Hepatic coccidiosis in the goat

Coccidial oocysts were seen in the bile from five goats infected with coccidia either naturally or artificially. The oocysts measured on average 21.3 by 18.3 microns and resembled those of Eimeria ninakohlyakimovae. Livers and gall bladders of infected animals showed various degrees of histopathological changes. In the worst case, bile had a thick consistency and contained blood and necrotic debris. Apart from those in the bile, oocysts were seen in liver smears and in the centrilobular vein in two histological sections. Forms resembling meronts and measuring on average 200 by 147 microns were seen in sections of bile duct.