乙肝藥物可能有效抗早衰疾病

StephenW

A hepatitis B drug could be effective against premature aging diseases
Massive Science
The ends of our DNA, called telomeres, get shorter as we age. Our cells lose a bit of telomere every time they divide. This shortening is a normal and needed process that serves a protective function against cancer. This is because the older our cells get, the more likely they are to have accumulated damage or mutations that make them function incorrectly. Telomere shortening helps to take old cells that are reaching their “best before date” off the shelf before they can cause trouble.

But this can backfire: cells can shorten their telomeres too quickly, age rapidly, and die. This is what causes a subset of genetic premature aging diseases, including idiopathic pulmonary fibrosis, forms of aplastic anemia, and a rare disease called dyskeratosis congenita. Unfortunately, there are currently no available drug-based therapies for treating telomere-driven premature aging diseases.

Now, a candidate drug has found a new potential purpose in treating premature aging disease.

This drug, called RG7834, was originally identified as an inhibitor of hepatitis B virus (HBV). While it has been found to be well-tolerated in short-term administration to living organisms (like rodents and primates), this drug does not cure HBV, and is not yet publicly available. Interestingly, the host cell proteins affected by RG7834 are two enzymes that modify many different RNAs. These enzymes can cause degradation of host cell RNA — so RG7834 keeps RNA around that the cell otherwise might get rid of.

StephenW

乙肝藥物可能有效抗早衰疾病
大規模科學
隨著年齡的增長，DNA的末端稱為端粒變短。每次分裂，我們的細胞都會失去一些端粒。這種縮短是正常且需要的過程，其具有針對癌症的保護功能。這是因為我們的細胞年齡越大，它們積累的損害或突變就越可能使它們無法正常運行。端粒縮短可以幫助將已經達到其“最佳日期”的舊電池從貨架上拿出來，以免引起麻煩。

但這會適得其反：細胞會過短地縮短其端粒，迅速衰老並死亡。這就是導致遺傳性過早衰老疾病的一部分的原因，包括特發性肺纖維化，再生障礙性貧血和罕見的先天性角化病。不幸的是，當前沒有可用的基於藥物的療法來治療端粒驅動的過早衰老疾病。

現在，候選藥物已經發現了治療過早衰老疾病的新潛在目的。

該藥物名為RG7834，最初被確定為乙型肝炎病毒（HBV）的抑製劑。雖然已發現對活生物體（如囓齒動物和靈長類動物）的短期給藥耐受性良好，但該藥物無法治愈HBV，並且尚未公開發售。有趣的是，受RG7834影響的宿主細胞蛋白是修飾許多不同RNA的兩種酶。這些酶可導致宿主細胞RNA降解-因此RG7834可將RNA保留在細胞周圍，否則該細胞可能會被清除。

StephenW

https://massivesci.com/articles/ ... re-aging-stem-cell/