## 3 Results
(**A**) (Control rats): shows normal appearance of the digits, and joint with no redness or swelling. (**B**) (AIA rats): shows severe swelling in the whole paw including the digits with deformities in all-paw digits. (**C**) (AIA + Walnut) and (**D**) (AIA + peanut): shows almost normal appearance of the back paws with reduced swelling and deformities in most of all digits. (**E**) (AIA + Cashew) and (**F**) (AIA + Hazelnut): shows improvement in the deformities of the digits but with the presence of some swelling. Effect of Different Nuts' Oil on Arthritis Score and Rheumatoid Factors (RFs) in Adjuvant-Induced Arthritis (AIA) Rat Model  
Figure 4A illustrates the changes in arthritis scores in AIA rats. AIA rats displayed a significant (\(p\) = 0.00) increase in their arthritis score versus the control group and rats in the nut oil groups. Although a reduction in the arthritis score has been observed in the AIA + walnut oil group (1.67 \(\pm\) 0.650) and the AIA + peanut oil group (1.87 \(\pm\) 0.361), the difference in arthritis score between these two groups was insignificant (\(p\) = 0.996) The arthritis scores in the AIA + cashew oil (5.97 \(\pm\) 0.680), and the AIA + hazelnut oil (6.82 \(\pm\) 0.527) groups were also significantly (\(p\) = 0.00) lesser than in the AIA rats. Figure 4B shows the effects of all treatments on the RF in all experimental groups. Serum levels of RF were significantly (\(p\) = 0.00) increased in the AIA model rats versus the controls. However, the RF levels were significantly (\(p\) \(\leq\) 0.05) decreased in the rat groups that received walnut, peanut, cashew, and hazelnut oils versus the AIA group (52.478 \(\pm\) 11.859 mIU/mL). The maximum decrease in the levels of RF was seen in the AIA + walnut oil (14.965 \(\pm\) 4.080 mIU/mL) and AIA + peanut oil (20.845 \(\pm\) 5.283 mIU/mL) groups with no significant (\(p\) = 0.862) difference between the two groups. The results were nearly the same for the two groups of AIA + cashew oil (33.612 \(\pm\) 6.024 mIU/mL) and AIA + hazelnut oil (33.539 \(\pm\) 3.925 mIU/mL); there was insignificant (\(p\) = 1.00) difference between them. Effect of Different Nuts' Oil on Serum Levels of Pro-Inflammatory Cytokines in Adjuvant-Induced Arthritis (AIA) Rat Model  
Figure 5A-C lists the effects of different nut oils on pro-inflammatory cytokines. As confirmed by the CFA-induced arthritis model, the pro-inflammatory cytokines TNF-\(\alpha\), IL-6, and IL-1\(\beta\) significantly increased (\(p\)\(\leq\) 0.05) in the AIA group versus the control group. The levels of all these markers reduced in the nut oil groups, which received the walnut, peanut, cashew, and hazelnut oils versus the AIA model rats. Parallel with the  
Figure 4: Effect of different nuts’ oil on arthritis score (**A**) and serum levels of rheumatoid factors (**B**) in adjuvant-induced arthritis (AIA) rats. The arthritis score was calculated on a scale of 0–4/paw (an overall of 16 for the four paws). Accordingly, score 0.0: swelling or redness; score 1: redness or swelling in one paw or digit (one joint); score 2: redness and swelling in 2 digits or joints; score 3: swelling and redness in more than two digits or joints; and score 4: swelling and redness in all joints or digits or the entire paw. Model: One-way analysis of variance (ANOVA) with a statistical significance assumed at \(p\)\(\leq\) 0.05 followed by [PERSON]’s HSD post hoc test for statistically significant \(p\)-value. Data are presented as mean \(\pm\) SD for \(n\) = 5 rats/groups. a: Different from the control rats. b: Significantly different from the adjuvant-induced arthritis model rats (AIA). c: Significantly different from AIA + walnut oil. d: Significantly different from AIA + peanut oil. previous observations in terms of RF results, the maximum decrease in the levels of TNF-\(\alpha\) was observed in the rats that received AIA + walnut oil (111.482 \(\pm\) 23.284 pg/mL) and AIA + peanut oil (122.485 \(\pm\) 9.813 pg/mL) with no significant (\(p\) = 0.974) difference in any of these parameters between the two groups.