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PubMed2026

Hippocampal teneurin-4 knockdown promotes depression-like behavioral phenotypes by disrupting oligodendrocyte differentiation in mice.

Depression is one of the most prevalent mental disorders worldwide. The limited clinical efficacy of current antidepressants highlights identifying new therapeutic targets. Emerging evidence suggests that dysfunction of oligodendrocyte lineage cells contributes to the pathophysiology of depression. Teneurin-4 (Tenm4), a transmembrane protein that promotes oligodendrocyte differentiation and myelination, has been implicated in psychiatric disorders in genome-wide association studies; however, its causal role remains unclear. To determine whether Tenm4 contributes to depressive-like behavioral phenotypes, we examined Tenm4 protein expression in mice exposed to repeated forced swimming stress and generated hippocampal Tenm4 knockdown (Tenm4KD) mice. Chronic stress reduced Tenm4 expression levels in the hippocampus. Mice with hippocampus-specific Tenm4KD exhibited depressive-like behaviors, accompanied by reduced hippocampal myelin basic protein. Importantly, administration of clemastine, a myelin formation promoter, inhibited the reduction of myelin and attenuated depression-like behavioral phenotypes. Immunohistochemical analysis showed that Tenm4KD significantly decreased the number of mature oligodendrocyte cells and increased in the number of oligodendrocyte precursor cells, without changes in the total number of oligodendrocyte lineage cells. This study provides the first evidence that hippocampal Tenm4 deficiency induces depression-like behavior phenotypes through impaired oligodendrocyte differentiation and promoting demyelination. Our results identify Tenm4 as a molecular regulator of stress-induced behavioral phenotypes and suggest that it might represent a potential therapeutic target for mood disorders associated with demyelination.

Animals↗
PubMed2026

Sex-dependent protective effects of microglial tumor necrosis factor on post-stroke inflammation and myelin injury.

Tumor necrosis factor (TNF) is rapidly induced after ischemic stroke, but its proposed cell-specific and sex-dependent functions during post-stroke inflammation remain insufficiently understood. Here, we investigated the role of microglia-derived TNF in the acute and subacute response to permanent middle cerebral artery occlusion (pMCAO). Tnf expression was transiently upregulated after stroke, becoming significant at 4 h, peaking at 12-24 h, and returning to baseline by 5 days. In situ hybridization confirmed strong Tnf expression in the infarct and peri-infarct regions. Whole-brain transcriptomic profiling showed that global TNF deficiency reshaped the early post-ischemic response, shifting it from microglia-associated phagocytic and wound-healing pathways toward an interferon-related inflammatory signature. To define the specific contribution of microglial TNF, we used inducible Cx3cr1CreER:Tnffl/fl mice. Microglial TNF deletion had no effect on infarct volume in males at 24 h or 5 days after pMCAO, but significantly increased infarct size in females at both time points. In both sexes, brain TNF levels peaked at 24 h and were significantly reduced in Cx3cr1CreER:Tnffl/fl mice, confirming microglia as a major source of early post-ischemic TNF. However, downstream consequences diverged by sex. At 5 days, male Cx3cr1CreER:Tnffl/fl mice showed reduced microglial reactivity and 18 kDa translocator protein (TSPO) signal, with no change in T-cell infiltration, and exhibited increased density of mature oligodendrocytes. In contrast, female Cx3cr1CreER:Tnffl/fl mice displayed enhanced microglial reactivity, increased TSPO binding, higher peri-infarct T-cell infiltration, and reduced oligodendrocyte density and myelin integrity. Together, these findings identify microglial TNF as a sex-dependent regulator of post-stroke inflammation and myelin injury.

Animals↗
PubMed2026

Flexible ureteroscopy with a flexible and negative suction ureteral access sheath versus traditional sheath for treatment of infectious upper urinary tract stones: A prospective, randomized controlled study.

To evaluate the efficacy and safety of the flexible ureteroscopy (fURS) with a flexible and negative suction ureteral access sheath (FANS) versus traditional sheath for patients with infectious upper urinary tract stones (IUUTS). A total of 185 patients were enrolled, with 93 assigned to the FANS group and 92 to the traditional UAS group. The primary outcome was the stone-free rate (SFR) at the first postoperative day. Secondary outcomes included the SFR at 30 days postoperatively, operative time, hemoglobin reduction, length of hospital stay, quality of life (QoL) improvement, incidence of ureteral stricture at 3 months, and surgery-related complications. No significant differences were observed between the two groups in baseline demographics or preoperative clinical characteristics (P&#x2009;>&#x2009;0.05). The FANS group had significantly lower white blood cell count, C-reactive protein, and procalcitonin levels at 6 and 24&#xa0;h postoperatively (all P&#x2009;<&#x2009;0.05). Mean operative time was significantly shorter (P&#x2009;<&#x2009;0.001), QoL improvement was obviously greater (P&#x2009;<&#x2009;0.001), and average hospital stay was shorter in the FANS group (P&#x2009;<&#x2009;0.001). The SFRs on postoperative day 1 and at 30 days were both significantly higher in the FANS group (both P&#x2009;<&#x2009;0.05). At 3 months, ureteral strictures occurred in three patients in the traditional UAS group and one in the FANS group, a difference that was not statistically significant (P&#x2009;>&#x2009;0.05). The overall complication rate was significantly lower in the FANS group (P&#x2009;<&#x2009;0.05). For patients with IUUTS, fURS combined with FANS effectively improves stone clearance efficiency and reduces the risk of postoperative infection.

Humans↗
PubMed2026

Retrograde intrarenal surgery with flexible and navigable suction access sheaths vs mini-percutaneous nephrolithotomy for large upper urinary tract stones: a&#xa0;systematic review and meta-analysis.

OBJECTIVE: To conduct a meta-analysis comparing the efficacy and perioperative outcomes of contemporary flexible and navigable suction access sheath-assisted retrograde intrarenal surgery (FANS-RIRS) against percutaneous nephrolithotomy (PCNL) for the management of large upper urinary tract stones, as despite technological advances in RIRS such as high-powered lasers and FANS that have substantially enhanced its performance, current guidelines continue to recommend&#x2009;PCNL as first-line treatment for renal stones >2cm. METHODS: MEDLINE, Embase, and the Cochrane Library were searched for studies performing direct comparisons of FANS-RIRS against PCNL in adult patients until September 2025. Primary outcomes included stone-free rates (SFRs) and need for ancillary procedures. Secondary outcomes included operative time, length of postoperative hospitalisation, and postoperative complications. RESULTS: A total of 10 studies (three randomised control trials, seven retrospective cohort studies) comprising 2347 patients were included; preoperative stone sizes were predominantly 2-3&#x2009;cm. All PCNL procedures in the studies included were performed as mini-PCNL. The SFRs for FANS-RIRS were comparable with mini-PCNL across all stone sizes (odds ratio [OR] 0.90, 95% confidence interval [CI] 0.70-1.17) and stones &#x2265;2&#x2009;cm (OR 0.80, 95% CI 0.60-1.08), with low heterogeneity. Ancillary procedures rates were similar (OR 1.22, 95% CI 0.61-2.44). FANS-RIRS was associated with significantly fewer overall complications, specifically smaller haemoglobin decline, need for transfusion, and shorter hospital stay. However, mini-PCNL demonstrated shorter operative times for stones &#x2265;2&#x2009;cm. Urosepsis rates were low and similar between both groups. Limitations include predominance of Asian studies, variability of practice, and inclusion of non-randomised studies. CONCLUSIONS: Contemporary FANS-RIRS achieves SFRs comparable to mini-PCNL even for 2-3&#x2009;cm stones, while offering superior safety profiles and shorter hospitalisation; this supports FANS-RIRS as a viable primary treatment in selected patients.

Humans↗
PubMed2026

F-URS with FANS versus mPCNL for 2-3&#x2009;cm UUTS: a RCT with a subgroup analysis of 2-2.5&#x2009;cm stones.

OBJECTIVE: To evaluate the safety and efficacy of flexible ureteroscopy (f-URS) with a flexible and navigable suction ureteral access sheath (FANS) compared with mini-percutaneous nephrolithotomy (mPCNL) in the treatment of 2-3&#x2009;cm upper urinary tract stones (UUTS), with a prespecified subgroup analysis for stones &#x2265;2 to <2.5&#x2009;cm. METHODS: This randomized controlled trial enrolled 326 patients with 2-3&#x2009;cm UUTS between June 2023 and December 2025. Patients were randomly assigned in a 1:1 ratio to undergo either f-URS with FANS or mPCNL. A prespecified subgroup analysis was conducted for stones measuring &#x2265;2 to <2.5&#x2009;cm. The primary outcomes were the immediate and 1-month stone-free rate (SFR). Secondary outcomes included the operative duration, decrease in haemoglobin, hospital stay, and complication rate. RESULTS: The baseline characteristics were comparable between the two groups. In the overall 2-3&#x2009;cm cohort, the FANS group achieved immediate and 1-month SFRs comparable to those of the mPCNL group. Although the operative time was longer in the FANS group, it was associated with significantly less haemoglobin loss and a shorter hospital stay, with no significant difference in infection-related complications. Notably, in the subgroup of stones &#x2265;2 to <2.5&#x2009;cm, the FANS group demonstrated a non-inferior SFR at both time points, and the operative time was not significantly longer than that of the mPCNL group. CONCLUSION: For 2-3&#x2009;cm UUTS, f-URS with FANS offers a SFR comparable to that of mPCNL, along with the advantages of reduced blood loss and shorter hospitalization. In the &#x2265;2 to <2.5&#x2009;cm subgroup, FANS shows comprehensive benefits over mPCNL. These findings support FANS as an effective alternative to mPCNL for 2-3&#x2009;cm stones and a potentially preferred option for stones measuring 2-2.5&#x2009;cm.

Humans↗
PubMed2026

Nimodipine in animal models of demyelination relevant to multiple sclerosis: a systematic review.

BACKGROUND: Multiple sclerosis (MS) is the most common inflammatory neurodegenerative disease in which axonal injury, neuronal death, and demyelination occur. Treatment for MS relapses remains limited, which alleviates acute loss of function but has no impact on long-term disability. This study aimed to perform a systematic review of the effects of nimodipine on experimental demyelination models, including experimental autoimmune encephalomyelitis (EAE) and Cuprizone models in rodents. METHODS: This study was conducted following the PRISMA statement. A systematic search was performed in PubMed, Scopus, the Cochrane Library, and Google Scholar. The primary outcome was EAE clinical disease severity (peak clinical score and/or cumulative disease burden). Secondary outcomes included relapse activity (when reported), histological myelin outcomes, oligodendrocyte lineage markers, neuroaxonal injury markers, and inflammatory readouts. Risk of bias was assessed using the SYRCLE tool. RESULTS: Out of 4660 results, 5 studies were included in the systematic review (four EAE studies and one cuprizone model). Nimodipine was administered using heterogeneous regimens (oral, intravenous, intraperitoneal, subcutaneous, or osmotic pump delivery; 1-30&#xa0;mg/kg/day). The included studies reported the variable effects of nimodipine on relapse-related outcomes, myelination, inflammatory processes, and neuroprotection in the EAE model of MS. Across EAE studies, nimodipine generally reduced clinical disease severity or cumulative burden, although relapse-related outcomes were inconsistent. CONCLUSIONS: Preclinical evidence suggests that nimodipine may attenuate disease severity and demyelination and may promote repair-related processes in rodent models relevant to MS. However, to evaluate the clinical applicability of nimodipine in MS patients, well-powered, transparently reported preclinical replication and early-phase clinical studies are required before clinical translation.

Animals↗
PubMed2026

Biallelic Variants in ATP1A4 Are Associated with Oligoasthenoteratozoospermia and Male Infertility.

Male infertility, often caused by structural and functional sperm defects, remains genetically unexplained in a substantial proportion of cases. ATP1A4 encodes a testis-specific isoform of the Na+, K+-ATPase, a membrane enzyme crucial for maintaining cellular ionic homeostasis. Previous studies on Atp1a4 knockout mice have demonstrated severe defects in sperm motility and flagellar architecture; however, the contribution of ATP1A4 variants to human male reproduction remains to be elucidated. In this study, we identified compound biallelic variants in ATP1A4, a missense variant (c.2578&#x2009;T>A, p.Tyr860Asn) and a frameshift variant (c.2582del, p.Gly861Aspfs*5), in a patient presenting with severe oligoasthenoteratozoospermia. Both variants markedly affected ATP1A4 protein expression. Morphological analyses revealed coiled and folded flagella, disrupted mitochondrial sheaths, and irregular head morphology in the patient's spermatozoa. Expression profiling revealed that ATP1A4 was highly enriched in post-meiotic spermatids and localized along the entire flagellum of mature sperm in both humans and mice, indicating a critical role in flagellar assembly and structural integrity. Notably, intracytoplasmic sperm injection (ICSI) in this patient resulted in low fertilization efficiency and failed implantation, suggesting a potential adverse impact of ATP1A4 deficiency on sperm functional competence beyond motility. These findings broaden the genetic spectrum of oligoasthenoteratozoospermia and highlight ATP1A4 as a potential gene associated with human male infertility.

Male↗