03130nas a2200445   4500000000100000008004100001260001200042653001200054653002500066653000900091653001000100653001700110653001600127653001400143653002000157100001100177700001400188700001400202700001500216700001200231700001500243700001100258700001300269700001300282700001100295700001300306700001600319700001300335700001400348700001400362700001400376700001700390700002100407245012400428856008100552300001100633490000700644520201900651022001402670       2021                            d  c01/202110a3β-HSD10aMycobacterium leprae10aPDIM10aPGL-I10acholestenone10acholesterol10aoxidation10areductive power1 aRosa T1 aMarques M1 aDeBoard Z1 aHutchins K1 aSilva C1 aMontague C1 aYuan T1 aAmaral J1 aAtella G1 aRosa P1 aMattos K1 aVanderVen B1 aLahiri R1 aSampson N1 aBrennan P1 aBelisle J1 aPessolani MC1 aBerrêdo-Pinho M00aReductive Power Generated by Mycobacterium leprae Through Cholesterol Oxidation Contributes to Lipid and ATP Synthesis.  uhttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC8355898/pdf/fcimb-11-709972.pdf  a7099720 v113 a<p>Upon infection, , an obligate intracellular bacillus, induces accumulation of cholesterol-enriched lipid droplets (LDs) in Schwann cells (SCs). LDs are promptly recruited to -containing phagosomes, and inhibition of this process decreases bacterial survival, suggesting that LD recruitment constitutes a mechanism by which host-derived lipids are delivered to intracellular . We previously demonstrated that  has preserved only the capacity to oxidize cholesterol to cholestenone, the first step of the normal cholesterol catabolic pathway. In this study we investigated the biochemical relevance of cholesterol oxidation on bacterial pathogenesis in SCs. Firstly, we showed that  increases the uptake of LDL-cholesterol by infected SCs. Moreover, fluorescence microscopy analysis revealed a close association between  and the internalized LDL-cholesterol within the host cell. By using  mutant strains complemented with  genes, we demonstrated that  coding for 3β-hydroxysteroid dehydrogenase (3β-HSD), but not  originally annotated as cholesterol oxidase (ChoD), was responsible for the cholesterol oxidation activity detected in . The 3β-HSD activity generates the electron donors NADH and NADPH that, respectively, fuel the  respiratory chain and provide reductive power for the biosynthesis of the dominant bacterial cell wall lipids phthiocerol dimycocerosate (PDIM) and phenolic glycolipid (PGL)-I. Inhibition of  3β-HSD activity with the 17β-[N-(2,5-di-t-butylphenyl)carbamoyl]-6-azaandrost-4-en-3one (compound 1), decreased bacterial intracellular survival in SCs. In conclusion, our findings confirm the accumulation of cholesterol in infected SCs and its potential delivery to the intracellular bacterium. Furthermore, we provide strong evidence that cholesterol oxidation is an essential catabolic pathway for  pathogenicity and point to 3β-HSD as a prime drug target that may be used in combination with current multidrug regimens to shorten leprosy treatment and ameliorate nerve damage.</p>  a2235-2988