1. Hippuric acid: Could became a barometer for frailty and geriatric syndromes?
Giulia De Simone, Claudia Balducci, Gianluigi Forloni, Roberta Pastorelli, Laura Brunelli Ageing Res Rev. 2021 Dec;72:101466. doi: 10.1016/j.arr.2021.101466. Epub 2021 Sep 22.
Aging is a natural biological event that has some downsides such as increased frailty, decline in cognitive and physical functions leading to chronical diseases, and lower quality of life. There is therefore a pressing need of reliable biomarkers to identify populations at risk of developing age-associated syndromes in order to improve their quality of life, promote healthy ageing and a more appropriate clinical management, when needed. Here we discuss the importance of hippuric acid, an endogenous co-metabolite, as a possible hallmark of human aging and age-related diseases, summarizing the scientific literature over the last years. Hippuric acid, the glycine conjugate of benzoic acid, derives from the catabolism by means of intestinal microflora of dietary polyphenols found in plant-based foods (e.g. fruits, vegetables, tea and coffee). In healthy conditions hippuric acid levels in blood and/or urine rise significantly during aging while its excretion drops in conditions related with aging, including cognitive impairments, rheumatic diseases, sarcopenia and hypomobility. This literature highlights the utility of hippuric acid in urine and plasma as a plausible hallmark of frailty, related to low fruit and vegetable intake and changes in gut microflora.
2. Medicinal Importance of Azo and Hippuric Acid Derivatives
Tehreem Tahir, Muhammad Ashfaq, Humna Asghar, Mirza I Shahzad, Rukhsana Tabassum, Areeba Ashfaq Mini Rev Med Chem. 2019;19(9):708-719. doi: 10.2174/1389557518666180727162018.
In this review, specific therapeutic and medicinal advantages including antiviral, antibacterial, antifungal and antitumor, strategies for drug designing, structure-activity relationship, advances in the syntheses of azo and hippuric acid derivatives of more than 50 compounds have been discussed since 2009-2018. It is found that phenyl-diazenyl azo derivatives and pyridinyl substituted hippuric acid derivatives showed promising antiretroviral potential. The incorporation of azo functionality to the respective quinolones and coumarin moieties and the insertion of thiocarbazone to hippuric acid displayed immense antibacterial activities. While, azo and hippuric acid derivatives of triazole and phenyl species gave maximum fungicidal as well as cytotoxic activities.
3. Plasmatic Hippuric Acid as a Hallmark of Frailty in an Italian Cohort: The Mediation Effect of Fruit-Vegetable Intake
Laura Brunelli, et al. J Gerontol A Biol Sci Med Sci. 2021 Nov 15;76(12):2081-2089. doi: 10.1093/gerona/glab244.
Frailty syndrome is an age-related condition involving a loss of resilience, susceptibility to adverse health outcomes, and poor quality of life. This study was conducted in the framework of InveCe.Ab, an ongoing longitudinal population-based study. Plasma from 130 older individuals (older adults aged 76-78 years) was analyzed and validated (on 303 participants) using mass spectrometry-based metabolomics approaches. Equivalence tests showed that metabolites from the central cellular metabolic pathways were equivalent in frail and fit participants. Hippuric acid was the only cometabolite that distinguished fit from frail older adults. Logistic regression analysis indicated that high hippuric acid levels are significantly associated with a reduction of the risk of frailty after 4 years. Mediation analysis using a Frailty Index, hippuric acid, and fruit-vegetable intake supported the role of fruit-vegetable consumption in the hippuric acid relationship with the Frailty Index. These data point to low plasma hippuric acid as a plausible hallmark of frailty status, associated with lower fruit-vegetable intakes.
