Codon-optimized FAM132b gene therapy prevents dietary obesity by blockading adrenergic response and insulin action
Codon-optimized FAM132b gene therapy prevents dietary obesity by blockading adrenergic response and insulin action
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密码子优化的 FAM132b 基因疗法通过阻断肾上腺素能反应和胰岛素作用来预防饮食肥胖
DOI：
10.1038/s41366-022-01189-x
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发表时间：
2022-08-03
影响因子：
4.9
通讯作者：
Liu，Weina
中科院分区：
文献类型：
--
作者：
Qi，Zhengtang;Xia，Jie;Liu，Weina
FAM132b(Myonectin)是一种肌源性运动肌动因子，在血液循环中具有激素活性，通过未知的受体调节铁稳态和脂代谢。在此，我们旨在探索腺相关病毒体内携带FAM132b的潜力，以开发一种治疗肥胖的基因疗法。方法通过A136T和P159A两个突变，构建腺相关病毒AAV9，诱导FAM132b过表达。然后，将AAV9经尾静脉注射给高脂饮食小鼠，观察小鼠的血糖稳态和肥胖发展情况。用结构生物学的方法预测FAM132b突变体的作用部位或受体。结果用AAV9治疗高脂饲料喂养的小鼠，改善了糖耐量和胰岛素抵抗，并导致体重、脂肪储备和脂肪细胞大小减少。密码子优化的FAM132b(CoFAM132b)降低了全身对肾上腺素(EPI)的血糖反应，并增加了脂肪组织对EPI的脂解反应。然而，通过shRNA敲除FAM132b显著增加了体内对EPI的血糖反应，降低了脂肪细胞对EPI的反应和脂肪组织的褐变。结构分析预测，含有A136T和P159A的FAM132b突变体可能与β-2肾上腺素能受体(ADRB2)形成弱结合，并可能对胰岛素和胰岛素受体复合体有更强的亲和力。结论本研究强调了FAM132b基因治疗结合密码子优化通过调节肾上腺素能反应和胰岛素作用来治疗肥胖的潜力。结构生物学分析和体内实验都表明，FAM132b突变体很可能阻断了肾上腺素能反应和胰岛素的作用。
BackgroundFAM132b (myonectin) has been identified as a muscle-derived myokine with exercise and has hormone activity in circulation to regulate iron homeostasis and lipid metabolism via unknown receptors. Here, we aim to explore the potential of adeno-associated virus to deliver FAM132b in vivo to develop a gene therapy against obesity.MethodsAdeno-associated virus AAV9 were engineered to induce overexpression of FAM132b with two mutations, A136T and P159A. Then, AAV9 was delivered into high-fat diet mice through tail vein, and glucose homeostasis and obesity development of mice were observed. Methods of structural biology were used to predict the action site or receptor of the FAM132b mutant.ResultsTreatment of high-fat diet-fed mice with AAV9 improved glucose intolerance and insulin resistance, and resulted in reductions in body weight, fat depot, and adipocyte size. Codon-optimized FAM132b (coFAM132b) reduced the glycemic response to epinephrine (EPI) in the whole body and increased the lipolytic response to EPI in adipose tissues. However, FAM132b knockdown by shRNA significantly increased the glycemic response to EPI in vivo and reduced adipocyte response to EPI and adipose tissue browning. Structural analysis predicted that the FAM132b mutant with A136T and P159A may form a weak bond with β2 adrenergic receptor (ADRB2) and may have more affinity for insulin and insulin-receptor complexes.ConclusionsOur study underscores the potential of FAM132b gene therapy with codon optimization to treat obesity by modulating the adrenergic response and insulin action. Both structural biological analysis and in vivo experiments suggest that the adrenergic response and insulin action are most likely blockaded by FAM132b mutants.