Table 3.
Incidence (%) and multiplicity (mean ± SE) of histopathological alterations in organs of Swiss H mice, as related to exposure to MCS and treatment with metformin
| Organ Histopathological alteration | Gender | Sham (45M + 49F) | MCS (55M + 54F) | MCS + metformin (37M + 37F) |
|---|---|---|---|---|
| Lung | ||||
| Emphysema | M | 1 (2.2%) | 6 (10.9%) | 2 (5.4%) |
| Incidence | F | 0 | 9 (16.7%)b | 2 (5.4%) |
| M + F | 1 (1.1%) | 15 (15.0%)c | 4 (5.4%) | |
| Alveolar epithelial hyperplasia | M | 2 (4.4%) | 17 (30.9%)c | 12 (32.4%)c |
| Incidence | F | 2 (4.1%) | 14 (25.9%)b | 12 (32.4%)c |
| M + F | 4 (4.3%) | 31 (28.4%)c | 24 (32.4%)c | |
| Bronchial epithelial hyperplasia | M | 1 (2.2%) | 4 (7.3%) | 4 (10.8%) |
| Incidence | F | 0 | 3 (5.6%) | 1 (2.7%) |
| M + F | 1 (1.1%) | 7 (6.4%) | 5 (6.8%) | |
| Blood vessel proliferation and hemangiomas | M | 2 (4.4%) | 5 (9.1%) | 6 (16.2%) |
| Incidence | F | 1 (2.0%) | 6 (11.1%)a | 1 (2.7%) |
| M + F | 3 (3.2%) | 13 (11.9%)a | 7 (9.5%) | |
| Microadenomas | M | 0 | 32 (58.2%)c | 9 (24.3%)c,d |
| Incidence | F | 0 | 29 (52.7%)c | 17 (45.9%)c |
| M + F | 0 | 61 (55.9%)c | 26 (35.1%)c,d | |
| Multiplicity (mean ± SE) | M | 0 | 7.7 ± 1.32c | 1.9 ± 0.60c,e |
| F | 0 | 10.2 ± 1.57c | 7.2 ± 1.72c | |
| M + F | 0 | 8.9 ± 1.03c | 4.5 ± 0.95c,d | |
| Adenomas | M | 1 (2.2%) | 14 (25.5%)b | 13 (35.1%)c |
| Incidence | F | 2 (4.1%) | 13 (24.1%)b | 10 (27.0%)c |
| M + F | 3 (3.2%) | 27 (24.8%)c | 23 (31.1%)c | |
| Multiplicity (mean ± SE) | M | 0.04 ± 0.04 | 4.1 ± 1.13c | 7.2 ± 1.95c |
| F | 0.06 ± 0.05 | 2.5 ± 1.03c | 4.7 ± 0.58c | |
| M + F | 0.05 ± 0.03 | 3.3 ± 0.76c | 5.9 ± 1.25c | |
| Malignant tumors | M | 0 | 7 (12.7%)a | 5 (13.5%) |
| Incidence | F | 0 | 6 (11.1%)a | 4 (10.8%) |
| M + F | 0 | 13 (11.9%)c | 9 (12.2%) | |
| Multiplicity (mean ± SE) | M | 0 | 0.4 ± 0.16a | 0.4 ± 0.21a |
| F | 0 | 0.3 ± 0.15a | 0.4 ± 0.21a | |
| M + F | 0 | 0.3 ± 0.11b | 0.4 ± 0.15b | |
| Liver | ||||
| Parenchymal degeneration | M | 1 (2.2%) | 3 (5.5%) | 1 (2.7%) |
| Incidence | F | 1 (2.0%) | 3 (5.6%) | 0 |
| M + F | 2 (2.1%) | 6 (5.5%) | 1 (1.4%) | |
| Kidney | ||||
| Tubular epithelial hyperplasia | M | 1 (2.2%) | 16 (29.1%)c | 0c |
| Incidence | F | 0 | 13 (24.1%)c | 4 (10.8%)a |
| M + F | 1 (1.1%) | 29 (26.6%)c | 4 (5.4%)e | |
| Urinary bladder | ||||
| Papillary epithelial hyperplasia | M | 1 (2.2%) | 7 (12.7%) | 4 (10.8%) |
| Incidence | F | 0 | 0 | 0 |
| M + F | 1 (1.1%) | 7 (6.4%)a | 4 (5.4%) | |
MCS, mainstream cigarette smoke.
Statistical analysis:
a
P < 0.05,
b
P < 0.01, and
c
P < 0.001, as compared with Sham;
d
P < 0.01 and
e
P < 0.001, as compared with MCS-exposed mice of the same gender, in the absence of metformin.