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Trikha Rastogi, S.

Publications and source records attributed to Trikha Rastogi, S..

2 recordsLinked to original sources

A bioenergetic basis for multiorgan dysfunction in sepsis

Sepsis is a life-threatening multiorgan dysfunction that develops from a maladaptive host response to infection1. With an estimated 49 million cases per year and [~]11 million related deaths2, sepsis is a global WHO health priority3. Failure to overcome sepsis morbidity and lethality4,5 calls for alternative therapeutic approaches6-8. Here we report that adipocyte lipolysis is vital to prevent the pathogenesis of sepsis in mice. This protective response is evolutionary conserved, producing a plasma lipidomic profile9,10 that reflects on the severity of clinical sepsis. Mechanistically, adipocyte lipolysis fuels energy metabolism to sustain adaptive thermoregulation to infection, via insulin production and insulin receptor (INSR) signaling in adipocytes. This metabolic-based defense strategy does not impact on bacterial burden, establishing disease tolerance to infection11-14. In conclusion, adipocyte lipolysis induces insulin to rewire energy metabolism and support organ function in response to infection.

pathology↗

A Metabolite-Based Resistance Mechanism Against Malaria

Whether jaundice, a common presentation of Plasmodium (P.) falciparum malaria (1-3) arising from the accumulation of circulating bilirubin, represents an adaptive or maladaptive response to Plasmodium spp. infection is not understood (1-3). We found that asymptomatic P. falciparum infection was associated with a >10-fold higher ratio of unconjugated bilirubin over parasite burden, compared to symptomatic malaria. Genetic suppression of bilirubin synthesis by biliverdin reductase A (BVRA) (4) increased parasite virulence and malaria mortality in mice. Accumulation of unconjugated bilirubin in plasma, via genetic inhibition of hepatic conjugation by UDP glucuronosyltransferase family 1 member A1 (UGT1A1) (5), was protective against malaria in mice. Unconjugated bilirubin inhibited P. falciparum proliferation in red blood cells (RBC) via a mechanism that suppressed mitochondrial pyrimidine synthesis. Moreover, unconjugated bilirubin inhibited hemozoin (Hz) crystallization and compromised the parasites food vacuole. In conclusion, jaundice represents a metabolic response to Plasmodium spp. infection that limits malaria severity.

immunology↗