Albumin/Globulin Ratio as Yin–Yang in Rheumatoid Arthritis and Its Correlation to Inflamm-Aging Cytokines

Yong Chen,1 Yanjuan Chen,2 Li Zhao,3 Hui He,3 Laiyou Wei,1 Wenjuan Lai,1 Jingxia Yuan,1 Xiaoping Hong,1 Lixiong Liu,1 Baojiang Wang,4 Kutty Selva Nandakumar,5,&ast; Dongzhou Liu1,&ast; 1Division of Rheumatology and Research, The Second Clinical Medical College, Jinan University (Shenzhen People’s Hospital), Shenzhen, Guangdong, People’s Republic of China; 2School of Basic Medicine, Jinan University, Guangzhou, Guangdong, People’s Republic of China; 3Division of Health Management, The Second Clinical Medical College, Jinan University (Shenzhen People’s Hospital), Shenzhen, Guangdong, People’s Republic of China; 4Shenzhen Maternity & Child Healthcare Hospital, Shenzhen, Guangdong, People’s Republic of China; 5Southern Medical University-Karolinska Institute United Medical Inflammation Center, Southern Medical University, Guangzhou, Guangdong, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Dongzhou LiuDivision of Rheumatology and Research, The Second Clinical Medical College, Jinan University (Shenzhen People’s Hospital), Shenzhen, Guangdong, People’s Republic of ChinaTel +86 183 2111 6879Email liu_dz2001@sina.comPurpose: Inflamm-aging is a novel-concept in rheumatoid arthritis (RA) with accelerating aging process. We try to find a correlation between serum albumin/globulin (A/G) ratio and clinical biochemical parameters, incidence of aging-related diseases (ARDs) as well as inflammaging-related molecules.Patients and Methods: Healthy controls (HC) and RA patients were compared with their clinical biochemical parameters including albumin and globulin levels, A/G ratio, and levels of serum lipids. Incidence of ARDs in RA was compared with A/G ratio, having a cut off value of 1.2. Expression levels of leptin and Trf2 genes in PBMCs, and inflammatory factors like IL-1β, IL-6, IL-8 and TNF-ɑ between HC and RA patients were compared, and correlated with the A/G ratio.Results: Compared to HC, RA patients had decreased levels of albumin, while globulin levels were found to be increased, which led to a significantly lower A/G ratio in RA patients. A/G ratio rather than ESR and CRP had significant correlation with dyslipidemia in RA patients. Patients with A/G < 1.2 had a higher risk of ARDs than patients with A/G > 1.2. The RR was 2.48 (95% CI: 1.79 to 3.64, p < 0.0001). In addition, A/G ratio has positively correlated to leptin and Trf2 expression, while an inverse correlation was observed with the levels of inflamm-aging related cytokines like IL-6, IL-8 and TNF-ɑ.Conclusion: A decreased A/G ratio in RA patients has significantly correlated with dyslipidemia and ARDs, as well as inflammaging- related adipokine and pro-inflammatory cytokines. Thus, A/G ratio could be a reliable marker for evaluating the inflammaging process during clinical management in ARDs.Keywords: inflammation, age-related disease, dyslipidemia, leptin, biomarker