Echinochrome A Reverses Kidney Abnormality and Reduces Blood Pressure in a Rat Model of Preeclampsia

Marine natural products

Covering: January to the end of December 2022This review covers the literature published in 2022 for marine natural products (MNPs), with 645 citations (633 for the period January to December 2022) referring to compounds isolated from marine microorganisms and phytoplankton, green, brown and red algae, sponges, cnidarians, bryozoans, molluscs, tunicates, echinoderms, the submerged parts of mangroves and other intertidal plants. The emphasis is on new compounds (1417 in 384 papers for 2022), together with the relevant biological activities, source organisms and country of origin. Pertinent reviews, biosynthetic studies, first syntheses, and syntheses that led to the revision of structures or stereochemistries, have been included. An analysis of NP structure class diversity in relation to biota source and biome is discussed.

Echinochrome A Prevents Diabetic Nephropathy by Inhibiting the PKC-Iota Pathway and Enhancing Renal Mitochondrial Function in db/db Mice

Echinochrome A (EchA) is a natural bioproduct extracted from sea urchins, and is an active component of the clinical drug, Histochrome®. EchA has antioxidant, anti-inflammatory, and antimicrobial effects. However, its effects on diabetic nephropathy (DN) remain poorly understood. In the present study, seven-week-old diabetic and obese db/db mice were injected with Histochrome (0.3 mL/kg/day; EchA equivalent of 3 mg/kg/day) intraperitoneally for 12 weeks, while db/db control mice and wild-type (WT) mice received an equal amount of sterile 0.9% saline. EchA improved glucose tolerance and reduced blood urea nitrogen (BUN) and serum creatinine levels but did not affect body weight. In addition, EchA decreased renal malondialdehyde (MDA) and lipid hydroperoxide levels, and increased ATP production. Histologically, EchA treatment ameliorated renal fibrosis. Mechanistically, EchA suppressed oxidative stress and fibrosis by inhibiting protein kinase C-iota (PKCι)/p38 mitogen-activated protein kinase (MAPK), downregulating p53 and c-Jun phosphorylation, attenuating NADPH oxidase 4 (NOX4), and transforming growth factor-beta 1 (TGFβ1) signaling. Moreover, EchA enhanced AMPK phosphorylation and nuclear factor erythroid-2-related factor 2 (NRF2)/heme oxygenase 1 (HO-1) signaling, improving mitochondrial function and antioxidant activity. Collectively, these findings demonstrate that EchA prevents DN by inhibiting PKCι/p38 MAPK and upregulating the AMPKα/NRF2/HO-1 signaling pathways in db/db mice, and may provide a therapeutic option for DN.