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Glycation is vital in terms of its damaging effect on macromolecules resulting in the formation of end products, which are highly reactive and cross‐linked irreversible structures, known as advanced glycation end products (AGEs). The continuous accumulation of AGEs is associated with severe diabetes and its associated ailments. Saccharides with their reducing ends can glycate amino acid side chains of proteins, among them glucose is well‐known for its potent glycating capability. However, other reducing sugars can be more reactive glycating agents than glucose. The D‐ribose is a pentose sugar‐containing an active aldehyde group in its open form and is responsible for affecting the biological processes of the cellular system. D‐ribose, a key component of many biological molecules, is more reactive than most reducing sugars. Protein glycation by reducing monosaccharides such as D‐ribose promotes the accelerated formation of AGEs that could lead to cellular impairments and dysfunctions. Also, under a physiological cellular state, the bioavailability rate of D‐ribose is much higher than that of glucose in diabetes, which makes this species much more active in protein glycation as compared with D‐glucose. Due to the abnormal level of D‐ribose in the biological system, the glycation of proteins with D‐ribose needs to be analyzed and addressed carefully. In the present study, human immunoglobulin G (IgG) was isolated and purified via affinity column chromatography. D‐ribose at 10 and 100 mM concentrations was used as glycating agent, for 1–12 days of incubation at 37°C. The postglycation changes in IgG molecule were characterized by UV‐visible and fluorescence spectroscopy, nitroblue tetrazolium assay, and various other physicochemical analyses for the confirmation of D‐ribose mediated IgG glycation. Significance statement: 1.D‐ribose‐induced glycation leads to structural perturbations in immunoglobulin G (IgG), the formation of IgG‐advanced glycation end products, and the generation of oxidative stress. 2.UV‐visible spectroscopy revealed the hyperchromicity of glycated IgG increases with the increase in the concentration of D‐ribose and time interval. 3.The early glycation products that is, Amadori products or ketoamines formed during D‐ribose mediated glycation of IgG were assessed by nitroblue tetrazolium assay and found to be increased initially in the first 5 days. 4.Hydroxymethylfurfural, carbonyl content, thiobarbituric acid reactive substances, and fluorescence intensity were found to be increased in glycated IgG as compared to the native analog. 5.Free lysine and arginine were found to be decreased in glycated IgG in comparison to the native conformer of the protein. [ABSTRACT FROM AUTHOR]

Rheumatoid arthritis (RA), a chronic inflammatory disease, and its exact aetiology is not defined clearly. The free radicals produced in large amount in RA are associated with alteration in molecular structure resulting in glycation of proteins. As a result of glycation, advanced glycation end products (AGEs) produced. In this study, collagen type II suspension was injected into Wistar rats to make RA model of rats. Simultaneously, hesperidin 50 mg kg−1 body weight was orally administrated to the rats for 21 days. X‐rays of the rat hind paws were analyzed and found to be significantly effective against bone loss after treatment with hesperindin. Nε‐(carboxymethyl)lysine (CML) and pentosidine (PTD) concentrations in collagen‐induced RA plasma were determined as 565.29 ± 30.15 and 37.23 ± 1.02 ng ml−1, respectively, while CML and PTD in IgG were 6.63 ± 0.44 ng mg−1 IgG and 425.33 ± 37.26 ng g−1 IgG, respectively. After treatment with hesperidin, the elevated levels of CML in plasma and in IgG were significantly (p < 0.001) lowered to 450.95 ± 15.05 mg ml−1 and 5.23 ± 0.27 ng mg−1 IgG, respectively. Similarly, concentrations of PTD in plasma and IgG of rats treated with hesperidin were 28.46 ± 1.20 ng ml−1 and 359.35 ± 31.11 ng g−1 IgG, respectively. Thus, after treatment with drug, plasma CML and IgG PTD levels were restored as 93% and 16%, respectively, through free radical scavenging activity of hesperidin resulting in alleviation of RA disease by decreasing the AGEs concentrations. Therefore, use of hesperidin may be useful to alleviate severity of RA disease. Significance statement: Collagen type II suspension was used to make a rheumatoid arthritis model of rat.Hesperidin treatment was effective against bone loss.Hesperidin effectively reduced the concentrations of advanced glycation end products like Nε‐(carboxymethyl)lysine and pentosidine.Treatment with hesperidin resulted in the alleviation of rheumatoid arthritis disease through free radical scavenging and antiglycation activities.Hesperidin may be useful to alleviate the severity of rheumatoid arthritis disease. [ABSTRACT FROM AUTHOR]