Effects of Piracetam and Hyperbaric Oxygen on Histopathological and Circulating Biochemical Responses Following Sciatic Nerve Crush Injury in Rats
Canoğlu UC, Yorulmaz IS, Gamsızkan M, İskender A, Alpay M, Sungur MA, Sheikhvatan M · 2026 · Medicina (Kaunas, Lithuania) 62(10)
Published 2026-10-01. Indexed 2026-10-28.
Reported findings and study design
After 14 days, piracetam, hyperbaric oxygen and their combination did not significantly improve axonal continuity, myelin regeneration or capillary formation. Piracetam increased fibroblast density and inflammatory-cell infiltration; selected circulating biochemical markers also changed. These early tissue and biomarker changes did not establish functional nerve recovery.
Dose, route and schedule
Piracetam 250 mg/kg/day intraperitoneally, divided into two 125 mg/kg injections approximately 12 hours apart for 14 days. Hyperbaric oxygen: 2.5 ATA for one hour daily for 14 days. Four groups: injury control, oxygen, piracetam and combination. Animal methods, not human doses.
Protocol source ↗ · Original full-text XML, methods and results checked
| Measure | Result | Comparison, timing and statistics |
|---|---|---|
| Animals and follow-up | 40 rats; four groups of 10; 14 days | |
| Nerve repair | No significant improvement in axonal continuity, myelin regeneration or capillary formation | |
| Fibroblast density | Higher with piracetam than untreated injury control | p=0.025 |
| Inflammatory-cell infiltration | Higher with piracetam and with the combination | Versus untreated injury control · p=0.037 and p=0.014, respectively |
| Neuron-specific enolase | Higher with piracetam than untreated injury control | p=0.006 |
Table 1. Proposed operational definitions for histopathological scoring.
| Histopathological Parameter | Score 1 | Score 2 | Score 3 |
|---|---|---|---|
| Axonal continuity | Marked disruption of axonal continuity, with extensive discontinuity or severe structural disorganization | Partial preservation of axonal continuity with areas of disruption or irregular organization | Predominantly preserved axonal continuity with relatively organized axonal structures |
| Fibroblast count/density | Markedly increased fibroblast density compared with the expected tissue appearance | Moderately increased fibroblast density | Low or minimally increased fibroblast density |
| Myelin sheath thickness or regeneration | Severe myelin loss, marked thinning, or minimal evidence of remyelination | Partial myelin preservation or intermediate evidence of remyelination | Relatively preserved myelin sheaths or prominent evidence of remyelination |
| Inflammatory cell count | Marked inflammatory-cell infiltration | Moderate inflammatory-cell infiltration | Minimal or absent inflammatory-cell infiltration |
| Capillary density | Markedly reduced capillary density or severe vascular alteration | Intermediate capillary density or moderate vascular alteration | Relatively preserved or increased capillary density with no major vascular alteration |
K: injury control; HBO: hyperbaric oxygen; P: piracetam. Values and units retained as printed; cell differences are not clinical treatment benefits.
Table 2. The descriptive statistics of histopathological scores among study groups.
| Histopathological Parameter | Group K | Group HBO | Group P | Group HBO + P | p-Value |
|---|---|---|---|---|---|
| Axonal continuity | 2.0 (2.0–2.8; 2–3) | 2.0 (2.0–2.0; 2–3) | 2.0 (2.0–2.0; 2–3) | 2.0 (2.0–2.0; 2–2) | 0.281 |
| Fibroblast score | 2.0 (2.0–2.8; 2–3) | 2.0 (2.0–2.0; 2–3) | 2.0 (2.0–2.0; 1–2) | 2.0 (2.0–2.0; 2–2) | 0.036 |
| Myelin sheath score | 2.0 (1.2–2.8; 1–3) | 2.0 (2.0–2.0; 2–3) | 2.0 (2.0–2.0; 2–3) | 2.0 (2.0–2.0; 2–2) | 0.931 |
| Inflammatory cell score | 3.0 (2.0–3.0; 2–3) | 2.0 (1.2–2.8; 1–3) | 2.0 (1.0–2.0; 1–3) | 2.0 (1.0–2.0; 1–2) | 0.011 |
| Capillary density score | 2.5 (1.0–3.0; 1–3) | 1.0 (1.0–1.8; 1–3) | 2.0 (2.0–2.0; 1–2) | 2.0 (1.0–2.8; 1–3) | 0.418 |
K: injury control; HBO: hyperbaric oxygen; P: piracetam. Values and units retained as printed; cell differences are not clinical treatment benefits.
Table 3. Comparison of serum biochemical parameters among the study groups.
| Biomarker (nmol/mL) | Group K | Group HBO | Group P | Group HBO + P | Overall p Value |
|---|---|---|---|---|---|
| HIF-1α | 0.838 ± 0.181 a | 0.571 ± 0.254 b | 0.445 ± 0.199 b | 0.540 ± 0.165 b | 0.001 |
| NSE | 0.609 ± 0.117 a | 0.742 ± 0.237 ab | 0.967 ± 0.344 b | 0.773 ± 0.124 ab | 0.011 |
| S100β | 1.499 ± 0.450 | 1.388 ± 0.474 | 1.053 ± 0.297 | 1.135 ± 0.332 | 0.070 |
K: injury control; HBO: hyperbaric oxygen; P: piracetam. Values are presented as mean ± standard deviation. Different superscript letters indicate statistically significant differences according to the post hoc multiple-comparison analysis.
Table 4. Post hoc pairwise comparison of HIF-1α and Neuron-specific enolase (NSE) levels among groups.
| HIF-1α | Post Hoc p-Value | NSENanomolar/mL | Post Hoc p-Value |
|---|---|---|---|
| Group K vs. Group HBO | 0.028 | Group K vs. Group HBO | 0.554 |
| Group K vs. Group P | 0.001 | Group K vs. Group P | 0.006 |
| Group K vs. Group HBO + P | 0.012 | Group K vs. Group HBO + P | 0.379 |
| Group HBO vs. Group P | 0.510 | Group HBO vs. Group P | 0.135 |
| Group HBO vs. Group HBO + P | 0.986 | Group HBO vs. Group HBO + P | 0.991 |
| Group P vs. Group HBO + P | 0.721 | Group P vs. Group HBO + P | 0.234 |
K: injury control; HBO: hyperbaric oxygen; P: piracetam. Values and units retained as printed; cell differences are not clinical treatment benefits.
Table 5. The factorial results of biochemical and histopathological outcomes.
| Outcome | Piracetam Main Effect | HBO Main Effect | Piracetam × HBO Interaction |
|---|---|---|---|
| HIF-1α | p = 0.006 | p = 0.041 | p = 0.018 |
| NSE | p = 0.021 | p = 0.486 | p = 0.032 |
| S100β | p = 0.064 | p = 0.721 | p = 0.284 |
| Axonal continuity | p = 0.412 | p = 0.738 | p = 0.563 |
| Myelin regeneration | p = 0.856 | p = 0.902 | p = 0.744 |
| Capillary formation | p = 0.227 | p = 0.381 | p = 0.196 |
| Fibroblast density | p = 0.044 | p = 0.309 | p = 0.082 |
| Inflammatory-cell infiltration | p = 0.017 | p = 0.221 | p = 0.049 |
K: injury control; HBO: hyperbaric oxygen; P: piracetam. Values and units retained as printed; cell differences are not clinical treatment benefits.
Rat injury model with a 14-day endpoint. Histological and biochemical changes are not proof of sustained functional recovery; the increased NSE and inflammatory measures must not be summarized as uniformly protective.
Source for the extracted data ↗ · Checked 2026-10-31
Molekul summary of the linked publication. Educational information, not medical advice. Seek qualified healthcare help for medical conditions.
Methods, limitations & source review
Study limitations
- Rat injury model with a 14-day endpoint. Histological and biochemical changes are not proof of sustained functional recovery; the increased NSE and inflammatory measures must not be summarized as uniformly protective.
Publication counts are not counts of independent trials. Reviews, translations and reports sharing participants may overlap. Findings apply to the studied preparation, population and endpoints.
Review depth: Original full-text XML, methods and results checked
Source access and review scope
Original full-text XML from Europe PMC checked on 31 October 2026, including methods and results. All five result tables retained; source units and statistical labels preserved.
Recorded source-check date: 2026-10-31. This date does not imply a completed systematic review.
Source type: Journal publication
Citation and original source
Original source: Canoğlu UC, Yorulmaz IS, Gamsızkan M, İskender A, Alpay M, Sungur MA, Sheikhvatan M. Effects of Piracetam and Hyperbaric Oxygen on Histopathological and Circulating Biochemical Responses Following Sciatic Nerve Crush Injury in Rats Medicina (Kaunas, Lithuania) 62(10) 2026.
Molekul research summary: https://molekul.io/research/oct31-42942435. Cite the original publication for its findings and this page when referring to Molekul’s summary or evidence appraisal.
Bibliography entry