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Anti‐cancer peptides (ACPs) represent a promising potential for cancer treatment, although their mechanisms need to be further elucidated to improve their application in cancer therapy. Lycosin‐I, a linear amphipathic peptide isolated from the venom of Lycosa singorensis, shows significant anticancer potential. Herein, it is found that Lycosin‐I, which can self‐assemble into a nanosphere structure, has a multimodal mechanism of action involving lipid binding for the selective and effective treatment of leukemia. Mechanistically, Lycosin‐I selectively binds to the K562 cell membrane, likely due to its preferential interaction with negatively charged phosphatidylserine, and rapidly triggers membrane lysis, particularly at high concentrations. In addition, Lycosin‐I induces apoptosis, cell cycle arrest in the G1 phase and ferroptosis in K562 cells by suppressing the PI3K‐AKT‐mTOR signaling pathway and activating cell autophagy at low concentrations. Furthermore, intraperitoneal injection of Lycosin‐I inhibits tumor growth of K562 cells in a nude mouse xenograft model without causing side effects. Collectively, the multimodal effect of Lycosin‐I can provide new insights into the mechanism of ACPs, and Lycosin‐I, which is characterized by high potency and specificity, can be a promising lead for the development of anti‐leukemia drugs. [ABSTRACT FROM AUTHOR]

Background: Chronic inflammation contributes to the progression of isoproterenol (ISO)‐induced heart failure (HF). Caspase‐associated recruitment domain (CARD) families are crucial proteins for initiation of inflammation in innate immunity. Nonetheless, the relevance of CARDs in ISO‐driven cardiac remodelling is little explored. Methods: This study utilized Card9−/− mice and reconstituted C57BL/6 mice with either Card9−/− or Otud1−/− marrow‐derived cells. Mechanistic studies were conducted in primary macrophages, cardiomyocytes, fibroblasts and HEK‐293T cells. Results: Here, we demonstrated that CARD9 was substantially upregulated in murine hearts infused with ISO. Either whole‐body CARD9 knockout or myeloid‐specific CARD9 deletion inhibited ISO‐driven murine cardiac inflammation, remodelling and dysfunction. CARD9 deficiency in macrophages prevented ISO‐induced inflammation and alleviated remodelling changes in cardiomyocytes and fibroblasts. Mechanistically, we found that ISO enhances the activity of CARD9 by upregulating ovarian tumour deubiquitinase 1 (OTUD1) in macrophages. We further demonstrated that OTUD1 directly binds to the CARD9 and then removes the K33‐linked ubiquitin from CARD9 to promote the assembly of the CARD9‐BCL10‐MALT1 (CBM) complex, without affecting CARD9 stability. The ISO‐activated CBM complex results in NF‐κB activation and macrophage‐based inflammatory gene overproduction, which then enhances cardiomyocyte hypertrophy and fibroblast fibrosis, respectively. Myeloid‐specific OTUD1 deletion also attenuated ISO‐induced murine cardiac inflammation and remodelling. Conclusions: These results suggested that the OTUD1‐CARD9 axis is a new pro‐inflammatory signal in ISO‐challenged macrophages and targeting this axis has a protective effect against ISO‐induced HF. Key points: Macrophage CARD9 was elevated in heart tissues of mice under chronic ISO administration.Either whole‐body CARD9 knockout or myeloid‐specific CARD9 deficiency protected mice from ISO‐induced inflammatory heart remodeling.ISO promoted the assembly of CBM complex and then activated NF‐κB signaling in macrophages through OTUD1‐mediated deubiquitinating modification.OTUD1 deletion in myeloid cells protected hearts from ISO‐induced injuries in mice. [ABSTRACT FROM AUTHOR]

Introduction: Type 2 diabetes and non-alcoholic fatty liver disease (NAFLD) often coexist and increase risk for developing liver fibrosis and diabetes complications if no effective measures are taken. Dietary intervention is known to be able to achieve diabetes remission, while evidence regarding the long-term effect on liver fat is limited for comorbidity management of type 2 diabetes and NAFLD. This study aims to investigate the long-term effect of a Chinese Medical Nutrition Therapy (CMNT) diet accompanied by intermittent energy restriction on reducing liver fat and glycated haemoglobin (HbA1c) in patients with type 2 diabetes and NAFLD., Methods and Analysis: This is a multicentre two-armed parallel randomised controlled trial study. 120 participants with type 2 diabetes and NAFLD will be recruited from the physical examination centres of multiple hospitals in China. Participants will be randomly allocated 1:1 to either the CMNT group or the usual care group. The CMNT group will be instructed to consume the provided specific meal replacement Chinese medicinal foods consisting of 6 cycles of 5 consecutive days followed by 10 days of regular food intake. The usual care group will be given standard dietary advice. Primary outcomes are changes in the controlled attenuation parameter value by transient elastography and HbA1c level. Secondary outcomes include differences in anthropometrics, clinical blood markers, questionnaires, gut microbiota and metabolomics. Further follow-up will be performed at 6 months, 1 year and 2 years., Ethics and Dissemination: The study protocol was approved by the Biomedical Research Ethics Committee of Hunan Agricultural University (BRECHAU20200235).The results will be disseminated via relevant peer-reviewed publications and conference presentations., Trial Registration Number: NCT05439226., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Kidney fibrosis is a prominent pathological feature of hypertensive kidney diseases (HKD). Recent studies have highlighted the role of ubiquitinating/deubiquitinating protein modification in kidney pathophysiology. Ovarian tumor domain-containing protein 6 A (OTUD6A) is a deubiquitinating enzyme involved in tumor progression. However, its role in kidney pathophysiology remains elusive. We aimed to investigate the role and underlying mechanism of OTUD6A during kidney fibrosis in HKD. The results revealed higher OTUD6A expression in kidney tissues of nephropathy patients and mice with chronic angiotensin II (Ang II) administration than that from the control ones. OTUD6A was mainly located in tubular epithelial cells. Moreover, OTUD6A deficiency significantly protected mice against Ang II-induced kidney dysfunction and fibrosis. Also, knocking OTUD6A down suppressed Ang II-induced fibrosis in cultured tubular epithelial cells, whereas overexpression of OTUD6A enhanced fibrogenic responses. Mechanistically, OTUD6A bounded to signal transducer and activator of transcription 3 (STAT3) and removed K63-linked-ubiquitin chains to promote STAT3 phosphorylation at tyrosine 705 position and nuclear translocation, which then induced profibrotic gene transcription in epithelial cells. These studies identified STAT3 as a direct substrate of OTUD6A and highlighted the pivotal role of OTUD6A in Ang II-induced kidney injury, indicating OTUD6A as a potential therapeutic target for HKD. NEW & NOTEWORTHY Ovarian tumor domain-containing protein 6 A (OTUD6A) knockout mice are protected against angiotensin II-induced kidney dysfunction and fibrosis. OTUD6A promotes pathological kidney remodeling and dysfunction by deubiquitinating signal transducer and activator of transcription 3 (STAT3). OTUD6A binds to and removes K63-linked-ubiquitin chains of STAT3 to promote its phosphorylation and activation, and subsequently enhances kidney fibrosis.