A Novel Diabetic Arthritic Model in Rats Induced by Streptozotocin, High-Fat Diet, and Complete Freund’s Adjuvant

Figures & data

Figure 1 (A) Diabetes induction by intraperitoneal streptozotocin injection. (B) Arthritis induction in diabetic rats. Complete-Freund’s Adjuvant was injected in ankle joint space by palpating a soft spot anterolateral to the anterior tibialis tendon in a manually distracted joint.

Table 1 Subject Characteristic (n=20)

Parameters	Group 1	Group 2	Group 3	Group 4	Group 5	p value
Initial blood glucose	110.75 ± 4.35	123.67 ± 4.93	132.00 ± 4.36	129.50±3.11	134.50 ± 6.45	<0.001
Body weight
- Initial	260.15 (206.3–263.5)	256.43 ± 8.75	175.53 ± 13.64	248.37 ± 20.08	253.87 ± 17.21	0.865
- After 2 weeks HFD	210.92 ± 124.41	333.4 (31.0–341.2)	335.26 ± 47.2	251.42 ± 147.69	264.47 ±157.37	0.061
Initial Ankle diameter	9.63 ± 0.49	8.83 ± 0.55	9.55 ± 0.05	9.72 ± 0.67	9.39 ± 0.32	0.197
LDL after HFD	2.45 ± 0.37^a	7.73 ± 3.85	5.80 ± 0.96	7.35±1.85	6.62 ± 1.75	0.051

Notes: ^aGroup 1 did not receive HFD treatment. Bold value represents statistically significant result.

Abbreviations: HFD, High-Fat Diet; LDL, Low-Density Lipoprotein.

Table 2 Comparison of Left Hind Limb Ankle Diameter Before and After Induction

Group	Pre CFA	Post CFA	p-value
1 (control)	9.64 ± 0.49	9.77 ± 0.46	0.089
2	8.83 ± 0.55	8.86 ± 0.58	0.423
3	9.55 ± 0.05	9.50 ± 0.10	0.225
4	9.72 ± 0.67	12.50±0.87	0.001
5	9.39 ± 0.32	11.85±0.74	0.019

Note: Bold value represents statistically significant result.

Table 3 Comparison to Contralateral Ankle and Control Group

Arthritic Group	4	5
Left	12.50 ± 0.87	11.85 ± 0.74
Right	9.67 ± 0.61	9.30 ± 0.41
Control	9.64 ± 0.49
Left to right comparison	0.001	0.021
Comparison to control group	0.003	0.037

Note: Bold values represent statistically significant result.

Figure 2 Ankle radiograph. (A) initial. (B) normal ankle after induction (Kellgren-Lawrence / KL 0) (C) KL-2, (D) KL-3, (E) KL-4.

Figure 3 Histology findings in normal ankle (A–C) vs grade 3 severely arthritic ankle (C and D) with Hematoxylin-Eosin staining. (A) Talo-tibial joint space (red asterisk) in normal ankle, total magnification (TM) 40x. (B) Healthy synovium consisted of 1–2 of synovial cell linings (yellow asterix). TM 100x. (C) Synovial connective tissue showed no infiltration of inflammatory cells. TM 400x. (D) Joint space was markedly reduced with irregularity of the articular cartilage. TM 40x. (E) Synovial cells hyperplasia (yellow asterix). TM 100x. (F) Dense inflammatory cells infiltrate in synovial connective tissue. TM 400x.

Figure 4 The boxplot graph showed a higher median in arthritic group (4 and 5) compared to control group (group 1) and diabetic only group (2, 3). Group 4 and 5 have a nearly identical medians, however, group 4 has more variability than group 5.